ASP.Net Interview Questions And Answers

What is the maximum number of cookies that can be allowed to a web site

2009-09-30T19:50:00.000-07:00

Which authentication mechanism allows you to connect to the database using the SYSDBA privilege?

2009-09-29T19:48:00.000-07:00

You are logged on to a client. You do not have a secure connection from your client to the host where your Oracle database is running. Which authentication mechanism allows you to connect to the database using the SYSDBA privilege?
A. Control file authentication
B. Password file authentication
C. Data dictionary authentication
D. Operating system authentication

Answer: B

Which property on a Combo Box do you set with a column name, prior to setting the DataSource, to display data in the combo box?

2009-09-29T19:47:00.000-07:00

DataTextField property.

Which control would you use if you needed to make sure the values in two different controls matched?

2009-09-28T19:47:00.000-07:00

CompareValidator control.

To test a Web service you must create a Windows application or Web application to consume this service?

2009-09-27T19:46:00.000-07:00

False, the web service comes with a test page and it provides HTTP-GET method to test.

What is ViewState?

2009-09-26T19:44:00.000-07:00

ViewState allows the state of objects (serializable) to be stored in a hidden field on the page. ViewState is transported to the client and back to the server, and is not stored on the server or any other external source. ViewState is used the retain the state of server-side objects between postabacks.

What is the lifespan for items stored in ViewState?

2009-09-25T19:43:00.000-07:00

Item stored in ViewState exist for the life of the current page. This includes postbacks (to the same page).

What does the "EnableViewState" property do? Why would I want it on or off?

2009-09-24T19:43:00.000-07:00

It allows the page to save the users input on a form across postbacks. It saves the server-side values for a given control into ViewState, which is stored as a hidden value on the page before sending the page to the clients browser. When the page is posted back to the server the server control is recreated with the state stored in viewstate.

What are the different types of Session state management options available with ASP.NET?

2009-09-23T19:43:00.000-07:00

ASP.NET provides In-Process and Out-of-Process state management. In-Process stores the session in memory on the web server. This requires the a "sticky-server" (or no load-balancing) so that the user is always reconnected to the same web server. Out-of-Process Session state management stores data in an external data source. The external data source may be either a SQL Server or a State Server service. Out-of-Process state management requires that all objects stored in session are serializable.

How to create a package for web application with components that shared with other applications?

2009-09-22T19:43:00.000-07:00

Create a setup project which produces a .msi file.
A shared component assembly must be given a strong name using the following steps:
1. Create a key pair using sn.exe -k on the command line
2. Add AssemblyKeyFileAttribute to the assembly file and set it to the full name and path of the key file generated in step 1.
3. Build the assembly
The setup program detects a strong named assembly and installs it into GAC on the client machine.

what is .net frame work?

2009-09-21T19:41:00.000-07:00

.Net framework is an environment provided on top of the OS which looks into
1. Memory management
2. Thread management
and provides
1. Language independence
2. Platform independence
It is defined by Microsoft as 'an environment for building, deploying and running web services and other applications. It consists of three main parts -- CLR, framework classes and ASP.Net'
.Net facilitates integration of code written for desktop applications with code written for web applications. It also facilitates creation of assemblies from code files written in different .net languages. It provides a common type system (CTS) for bringing data types of all languages on a common platform.

What is difference between Authentication and Authorization?

2009-09-20T19:39:00.000-07:00

Authentication-->Checking the validity.Ex:A creditcard validation by Verisign.It is called authenticating the CreditCard

Authorization-->Giving some rights -Ex:I authorize mr.Rahul to sign some papers realted with my bank accounts

Explain Assemblies?,Difference between Panel and GroupBox?,Differences between ASP and ASP.NET

2009-09-19T19:39:00.000-07:00

Assemblies are single deployable unit which consist of classes structures and interface.they consist of metadata which desrcibes assembly version ,name ,type etc. They are known as logical DLL's .
panel are scrollable and in panels captions can not be displayed.
it is vice versa incase of group box

Asp is not compiled that is interperated where as ASP.net is compiled.

ASSEMBLIES

2009-09-18T19:39:00.000-07:00

Assemblies are the building blocks of .NET Framework applications; they form the fundamental unit of deployment, version control, reuse, activation scoping, and security permissions. An assembly is a collection of types and resources that are built to work together and form a logical unit of functionality. An assembly provides the common language runtime with the information it needs to be aware of type implementations. To the runtime, a type does not exist outside the context of an assembly.

What is the Subquery ?

2009-09-17T19:39:00.000-07:00

Sub query is a query whose return values are used in filtering conditions of the main query.

What is the difference between excute query and excute nonquery.?

2009-09-16T19:38:00.000-07:00

Execute Query is the method which is used to return the result of the command like select Query. That is Update Query. The Execute Non Query
is used to return the Query os the statement like the update Delete Insert which returns No data

Whats the use of @ Register directives ?

2009-09-15T19:36:00.000-07:00

@ Register Associates aliases with namespaces and class names for concise notation in custom server control syntax.
<%@ Register tagprefix="tagprefix" Namespace="namespace" Assembly="assembly" %><%@ Register tagprefix="tagprefix" Tagname="tagname" Src="pathname" %>
Attributes tagprefix An alias to associate with a namespace.
tagname An alias to associate with a class.
Namespace The namespace to associate with tagprefix.
Src The location (relative or absolute) of the declarative User Control file to associate with the tagprefix:tagname pair.
Assembly The assembly in which the namespace that you are associating with tagprefix resides.
Note The assembly name does not include a file name extension.

In DataGrid, is it possible to add rows one by one at runtime. That means after entering data in one row next row will be added.

2009-09-14T19:37:00.000-07:00

Yes, for this you have to use datatable and after inserting the first row in datatable u have to bind that datatable to the grid and next time , first u have to add the row in datatable and next bind it to datagrid. keep on doing.
u have to maintain the datatable state

What property must you set, and what method must you call in your code, in order to bind the data from a data source to the Repeater control?

2009-09-13T19:35:00.000-07:00

You must set the DataSource property and call the DataBind method.

How can you provide an alternating color scheme in a Repeater control?

2009-09-12T19:33:00.000-07:00

Use the AlternatingItemTemplate.

Which template must you provide, in order to display data in a Repeater control?

2009-09-11T19:35:00.000-07:00

ItemTemplate.

Can you edit data in the Repeater control?

2009-09-10T19:35:00.000-07:00

No, it just reads the information from its data source.

Which method do you invoke on the DataAdapter control to load your generated dataset with data?

2009-09-09T19:34:00.000-07:00

The Fill() method.

Whats MSIL, and why should my developers need an appreciation of it if at all?

2009-09-08T19:34:00.000-07:00

MSIL is the Microsoft Intermediate Language. All .NET compatible languages will get converted to MSIL. MSIL also allows the .NET Framework to JIT compile the assembly on the installed computer.

Explain what a diffgram is, and a good use for one?

2009-09-07T19:33:00.000-07:00

The DiffGram is one of the two XML formats that you can use to render DataSet object contents to XML. A good use is reading database data to an XML file to be sent to a Web Service.

Describe the difference between inline and code behind.

2009-09-06T19:33:00.000-07:00

Inline code written along side the html in a page. Code-behind is code written in a separate file and referenced by the .aspx page.

Whats an assembly?

2009-09-05T19:29:00.000-07:00

Assemblies are the building blocks of the .NET framework. Overview of assemblies from MSDN

Can you explain what inheritance is and an example of when you might use it?

2009-09-04T19:29:00.000-07:00

When you want to inherit (use the functionality of) another class. Example: With a base class named Employee, a Manager class could be derived from the Employee base class.

What are the Application_Start and Session_Start subroutines used for?

2009-09-03T19:28:00.000-07:00

This is where you can set the specific variables for the Application and Session objects.

What is the Global.asax used for?

2009-09-02T19:27:00.000-07:00

The Global.asax (including the Global.asax.cs file) is used to implement application and session level events.

Can you explain the difference between an ADO.NET Dataset and an ADO Recordset?

2009-09-01T19:27:00.000-07:00

Valid answers are:
· A DataSet can represent an entire relational database in memory, complete with tables, relations, and views.
· A DataSet is designed to work without any continuing connection to the original data source.
· Data in a DataSet is bulk-loaded, rather than being loaded on demand.
· There's no concept of cursor types in a DataSet.
· DataSets have no current record pointer You can use For Each loops to move through the data.
· You can store many edits in a DataSet, and write them to the original data source in a single operation.
· Though the DataSet is universal, other objects in ADO.NET come in different versions for different data sources.

What is the difference between Server.Transfer and Response.Redirect? Why would I choose one over the other?

2009-08-31T19:26:00.000-07:00

Server.Transfer transfers page processing from one page directly to the next page without making a round-trip back to the client's browser. This provides a faster response with a little less overhead on the server. Server.Transfer does not update the clients url history list or current url. Response.Redirect is used to redirect the user's browser to another page or site. This performas a trip back to the client where the client's browser is redirected to the new page. The user's browser history list is updated to reflect the new address.

Should user input data validation occur server-side or client-side? Why?

2009-08-30T19:26:00.000-07:00

All user input data validation should occur on the server at a minimum. Additionally, client-side validation can be performed where deemed appropriate and feasable to provide a richer, more responsive experience for the user.

What type of code (server or client) is found in a Code-Behind class?

2009-08-29T19:26:00.000-07:00

The answer is server-side code since code-behind is executed on the server. However, during the code-behind's execution on the server, it can render client-side code such as JavaScript to be processed in the clients browser. But just to be clear, code-behind executes on the server, thus making it server-side code.

Explain the differences between Server-side and Client-side code?

2009-08-28T19:26:00.001-07:00

Server-side code executes on the server. Client-side code executes in the client's browser.

Explain the differences between Server-side and Client-side code?

2009-08-28T19:26:00.000-07:00

Server-side code executes on the server. Client-side code executes in the client's browser.

What data types do the RangeValidator control support

2009-08-27T19:25:00.000-07:00

?
Integer, String, and Date.

Suppose you want a certain ASP.NET function executed on MouseOver for a certain button. Where do you add an event handler?

2009-08-26T19:25:00.000-07:00

Add an OnMouseOver attribute to the button. Example: btnSubmit.Attributes.Add("onmouseover","someClientCodeHere();");

What’s a bubbled event?

2009-08-25T19:25:00.000-07:00

When you have a complex control, like DataGrid, writing an event processing routine for each object (cell, button, row, etc.) is quite tedious. The controls can bubble up their eventhandlers, allowing the main DataGrid event handler to take care of its constituents.

What’s the difference between Codebehind="MyCode.aspx.cs" andSrc="MyCode.aspx.cs"?

2009-08-24T19:24:00.000-07:00

CodeBehind is relevant to Visual Studio.NET only.

Where on the Internet would you look for Web services?

2009-08-23T19:46:00.000-07:00

http://www.uddi.org

Where do you store the information about the user’s locale?

2009-08-23T19:24:00.000-07:00

System.Web.UI.Page.Culture

A Web service can only be written in .NET?

2009-08-22T19:46:00.000-07:00

False

What namespace does the Web page belong in the .NET Framework class hierarchy?

2009-08-22T19:22:00.000-07:00

System.Web.UI.Page

How many classes can a single .NET DLL contain?

2009-08-21T19:44:00.000-07:00

It can contain many classes.

When during the page processing cycle is ViewState available?

2009-08-21T19:24:00.000-07:00

After the Init() and before the Page_Load(), or OnLoad() for a control.

What is the transport protocol you use to call a Web service?

2009-08-20T19:45:00.000-07:00

SOAP (Simple Object Access Protocol) is the preferred protocol.

What methods are fired during the page load?

2009-08-20T19:22:00.000-07:00

Init() - when the page is instantiated
Load() - when the page is loaded into server memory
PreRender() - the brief moment before the page is displayed to the user as HTML
Unload() - when page finishes loading.

What does WSDL stand for?

2009-08-19T19:44:00.000-07:00

Web Services Description Language.

What’s the difference between Response.Write() andResponse.Output.Write()?

2009-08-19T19:22:00.000-07:00

Response.Output.Write() allows you to write formatted output.

What do you mean by authentication and authorization

2009-08-18T19:40:00.000-07:00

Simple answer to this is as follows Authentication is process of finding whether the user is valid.Example username and password u enter in mail page.That process is authentication Authorization is the process of holding rights for particular task.Example: Usually admin have right to install software in companies and others are not granted this right.

Describe the role of inetinfo.exe, aspnet_isapi.dll andaspnet_wp.exe in the page loading process.

2009-08-18T19:21:00.000-07:00

inetinfo.exe is theMicrosoft IIS server running, handling ASP.NET requests among other things.When an ASP.NET request is received (usually a file with .aspx extension), the ISAPI filter aspnet_isapi.dll takes care of it by passing the request tothe actual worker process aspnet_wp.exe

Interview Questions ASP.NET

2008-11-12T01:30:00.000-08:00

Interview Questions
ASP.NET
1. Describe the role of inetinfo.exe, aspnet_isapi.dll andaspnet_wp.exe in the
page loading process. inetinfo.exe is theMicrosoft IIS server running, handling
ASP.NET requests among other things.When an ASP.NET request is received
(usually a file with .aspx extension),the ISAPI filter aspnet_isapi.dll takes care
of it by passing the request tothe actual worker process aspnet_wp.exe.
2. What’s the difference between Response.Write()
andResponse.Output.Write()? The latter one allows you to write
formattedoutput.
3. What methods are fired during the page load? Init() - when the pageis
instantiated, Load() - when the page is loaded into server memory,PreRender() -
the brief moment before the page is displayed to the user asHTML, Unload() -
when page finishes loading.
4. Where does the Web page belong in the .NET Framework class
hierarchy?System.Web.UI.Page
5. Where do you store the information about the user’s locale?
System.Web.UI.Page.Culture
6. What’s the difference between Codebehind="MyCode.aspx.cs"
andSrc="MyCode.aspx.cs"? CodeBehind is relevant to Visual Studio.NET
only.
7. What’s a bubbled event? When you have a complex control, like DataGrid,
writing an event processing routine for each object (cell, button, row, etc.) is
quite tedious. The controls can bubble up their eventhandlers, allowing the main
DataGrid event handler to take care of its constituents.
8. Suppose you want a certain ASP.NET function executed on MouseOver
overa certain button. Where do you add an event handler? It’s the
Attributesproperty, the Add function inside that property. So
btnSubmit.Attributes.Add("onMouseOver","someClientCod
e();")
9. What data type does the RangeValidator control support? Integer,String and
Date.
10. Explain the differences between Server-side and Client-side code? Serverside
code runs on the server. Client-side code runs in the clients’ browser.
11. What type of code (server or client) is found in a Code-Behind class?
Server-side code.
12. Should validation (did the user enter a real date) occur server-side or
client-side? Why? Client-side. This reduces an additional request to the server
to validate the users input.
13. What does the "EnableViewState" property do? Why would I want it on or
off? It enables the viewstate on the page. It allows the page to save the users
input on a form.
14. What is the difference between Server.Transfer and Response.Redirect?
Why would I choose one over the other? Server.Transfer is used to post a
form to another page. Response.Redirect is used to redirect the user to another
page or site.
15. Can you explain the difference between an ADO.NET Dataset and an ADO
Recordset?
· A DataSet can represent an entire relational database in memory,
complete with tables, relations, and views.
· A DataSet is designed to work without any continuing connection to
the original data source.
· Data in a DataSet is bulk-loaded, rather than being loaded on
demand.
· There's no concept of cursor types in a DataSet.
· DataSets have no current record pointer You can use For Each
loops to move through the data.
· You can store many edits in a DataSet, and write them to the
original data source in a single operation.
· Though the DataSet is universal, other objects in ADO.NET come in
different versions for different data sources.
16. Can you give an example of what might be best suited to place in the
Application_Start and Session_Start subroutines? This is where you can set
the specific variables for the Application and Session objects.
17. If I’m developing an application that must accommodate multiple security
levels though secure login and my ASP.NET web application is spanned
across three web-servers (using round-robin load balancing) what would be
the best approach to maintain login-in state for the users? Maintain the login
state security through a database.
18. Can you explain what inheritance is and an example of when you might use
it? When you want to inherit (use the functionality of) another class. Base Class
Employee. A Manager class could be derived from the Employee base class.
19. Whats an assembly? Assemblies are the building blocks of the .NET
framework. Overview of assemblies from MSDN
20. Describe the difference between inline and code behind. Inline code written
along side the html in a page. Code-behind is code written in a separate file and
referenced by the .aspx page.
21. Explain what a diffgram is, and a good use for one? The DiffGram is one of
the two XML formats that you can use to render DataSet object contents to
XML. For reading database data to an XML file to be sent to a Web Service.
22. Whats MSIL, and why should my developers need an appreciation of it if
at all? MSIL is the Microsoft Intermediate Language. All .NET compatible
languages will get converted to MSIL.
23. Which method do you invoke on the DataAdapter control to load your
generated dataset with data? The .Fill() method
24. Can you edit data in the Repeater control? No, it just reads the information
from its data source
25. Which template must you provide, in order to display data in a Repeater
control? ItemTemplate
26. How can you provide an alternating color scheme in a Repeater control?
Use the AlternatingItemTemplate
27. What property must you set, and what method must you call in your code,
in order to bind the data from some data source to the Repeater control?
You must set the DataSource property and call the DataBind method.
28. What base class do all Web Forms inherit from? The Page class.
29. Name two properties common in every validation control?
ControlToValidate property and Text property.
30. What tags do you need to add within the asp:datagrid tags to bind columns
manually? Set AutoGenerateColumns Property to false on the datagrid tag
31. What tag do you use to add a hyperlink column to the DataGrid?

32. What is the transport protocol you use to call a Web service? SOAP is the
preferred protocol.
33. True or False: A Web service can only be written in .NET? False
34. What does WSDL stand for? (Web Services Description Language)
35. Where on the Internet would you look for Web services?
(http://www.uddi.org)
36. Which property on a Combo Box do you set with a column name, prior to
setting the DataSource, to display data in the combo box? DataTextField
property
37. Which control would you use if you needed to make sure the values in two
different controls matched? CompareValidator Control
38. True or False: To test a Web service you must create a windows application
or Web application to consume this service? False, the webservice comes
with a test page and it provides HTTP-GET method to test.
39. How many classes can a single .NET DLL contain? It can contain many
classes.

ASP.NET

2008-10-20T02:49:00.000-07:00

ASP.NET is a set of technologies in the Microsoft .NET Framework for building Web applications and XML Web Services. ASP.NET pages execute on the server and generate markup such as HTML, WML or XML that is sent to a desktop or mobile browser. ASP.NET pages use a compiled, event-driven programming model that improves performance and enables the separation of application logic and user interface. ASP.NET pages and ASP.NET XML Web Services files contain server-side logic (as opposed to client side logic) written in Visual Basic .NET, C# .NET, or any .NET compatible language. Web applications and XML Web Services take advantage of the features of the common language runtime, such as type safety, inheritance, language interoperability, versioning, and integrated security.

What is the .NET Framework?

The Microsoft .NET Framework is a platform for building, deploying, and running Web Services and applications. It provides a highly productive, standards-based, multi-language environment for integrating existing investments with next-generation applications and services as well as the agility to solve the challenges of deployment and operation of Internet-scale applications. The .NET Framework consists of three main parts: the common language runtime, a hierarchical set of unified class libraries, and a componentized version of Active Server Pages called ASP.NET.

Runtime Technical Questions

Terminology

What is the common language runtime (CLR)?

The common language runtime is the execution engine for .NET Framework applications.

It provides a number of services, including the following:

Code management (loading and execution)

Application memory isolation

Verification of type safety

Conversion of IL to native code

Access to metadata (enhanced type information)

Managing memory for managed objects

Enforcement of code access security

Exception handling, including cross-language exceptions

Interoperation between managed code, COM objects, and pre-existing DLLs (unmanaged code and data)

Automation of object layout

Support for developer services (profiling, debugging, and so on)

What is the common type system (CTS)?

The common type system is a rich type system, built into the common language runtime, that supports the types and operations found in most programming languages. The common type system supports the complete implementation of a wide range of programming languages.

What is the Common Language Specification (CLS)?

The Common Language Specification is a set of constructs and constraints that serves as a guide for library writers and compiler writers. It allows libraries to be fully usable from any language supporting the CLS, and for those languages to integrate with each other. The Common Language Specification is a subset of the common type system. The Common Language Specification is also important to application developers who are writing code that will be used by other developers. When developers design publicly accessible APIs following the rules of the CLS, those APIs are easily used from all other programming languages that target the common language runtime.

What is the Microsoft Intermediate Language (MSIL)?

MSIL is the CPU-independent instruction set into which .NET Framework programs are compiled. It contains instructions for loading, storing, initializing, and calling methods on objects.

Combined with metadata and the common type system, MSIL allows for true cross-language integration.

Prior to execution, MSIL is converted to machine code. It is not interpreted.

What is managed code and managed data?

Managed code is code that is written to target the services of the common language runtime (see What is the Common Language Runtime?). In order to target these services, the code must provide a minimum level of information (metadata) to the runtime. All C#, Visual Basic .NET, and JScript .NET code is managed by default. Visual Studio .NET C++ code is not managed by default, but the compiler can produce managed code by specifying a command-line switch (/CLR).

Closely related to managed code is managed data—data that is allocated and de-allocated by the common language runtime's garbage collector. C#, Visual Basic, and JScript .NET data is managed by default. C# data can, however, be marked as unmanaged through the use of special keywords. Visual Studio .NET C++ data is unmanaged by default (even when using the /CLR switch), but when using Managed Extensions for C++, a class can be marked as managed by using the __gc keyword. As the name suggests, this means that the memory for instances of the class is managed by the garbage collector. In addition, the class becomes a full participating member of the .NET Framework community, with the benefits and restrictions that brings. An example of a benefit is proper interoperability with classes written in other languages (for example, a managed C++ class can inherit from a Visual Basic class). An example of a restriction is that a managed class can only inherit from one base class.

Assemblies

What is an assembly?

An assembly is the primary building block of a .NET Framework application. It is a collection of functionality that is built, versioned, and deployed as a single implementation unit (as one or more files). All managed types and resources are marked either as accessible only within their implementation unit, or as accessible by code outside that unit.

Assemblies are self-describing by means of their manifest, which is an integral part of every assembly. The manifest:

Establishes the assembly identity (in the form of a text name), version, culture, and digital signature (if the assembly is to be shared across applications).

Defines what files (by name and file hash) make up the assembly implementation.

Specifies the types and resources that make up the assembly, including which are exported from the assembly.

Itemizes the compile-time dependencies on other assemblies.

Specifies the set of permissions required for the assembly to run properly.

This information is used at run time to resolve references, enforce version binding policy, and validate the integrity of loaded assemblies. The runtime can determine and locate the assembly for any running object, since every type is loaded in the context of an assembly. Assemblies are also the unit at which code access security permissions are applied. The identity evidence for each assembly is considered separately when determining what permissions to grant the code it contains.

The self-describing nature of assemblies also helps makes zero-impact install and XCOPY deployment feasible.

What are private assemblies and shared assemblies?

A private assembly is used only by a single application, and is stored in that application's install directory (or a subdirectory therein). A shared assembly is one that can be referenced by more than one application. In order to share an assembly, the assembly must be explicitly built for this purpose by giving it a cryptographically strong name (referred to as a strong name). By contrast, a private assembly name need only be unique within the application that uses it.

By making a distinction between private and shared assemblies, we introduce the notion of sharing as an explicit decision. Simply by deploying private assemblies to an application directory, you can guarantee that that application will run only with the bits it was built and deployed with. References to private assemblies will only be resolved locally to the private application directory.

There are several reasons you may elect to build and use shared assemblies, such as the ability to express version policy. The fact that shared assemblies have a cryptographically strong name means that only the author of the assembly has the key to produce a new version of that assembly. Thus, if you make a policy statement that says you want to accept a new version of an assembly, you can have some confidence that version updates will be controlled and verified by the author. Otherwise, you don't have to accept them.

For locally installed applications, a shared assembly is typically explicitly installed into the global assembly cache (a local cache of assemblies maintained by the .NET Framework). Key to the version management features of the .NET Framework is that downloaded code does not affect the execution of locally installed applications. Downloaded code is put in a special download cache and is not globally available on the machine even if some of the downloaded components are built as shared assemblies.

The classes that ship with the .NET Framework are all built as shared assemblies.

If I want to build a shared assembly, does that require the overhead of signing and managing key pairs?

Building a shared assembly does involve working with cryptographic keys. Only the public key is strictly needed when the assembly is being built. Compilers targeting the .NET Framework provide command line options (or use custom attributes) for supplying the public key when building the assembly. It is common to keep a copy of a common public key in a source database and point build scripts to this key. Before the assembly is shipped, the assembly must be fully signed with the corresponding private key. This is done using an SDK tool called SN.exe (Strong Name).

Strong name signing does not involve certificates like Authenticode does. There are no third party organizations involved, no fees to pay, and no certificate chains. In addition, the overhead for verifying a strong name is much less than it is for Authenticode. However, strong names do not make any statements about trusting a particular publisher. Strong names allow you to ensure that the contents of a given assembly haven't been tampered with, and that the assembly loaded on your behalf at run time comes from the same publisher as the one you developed against. But it makes no statement about whether you can trust the identity of that publisher.

What is the difference between a namespace and an assembly name?

A namespace is a logical naming scheme for types in which a simple type name, such as MyType, is preceded with a dot-separated hierarchical name. Such a naming scheme is completely under the control of the developer. For example, types MyCompany.FileAccess.A and MyCompany.FileAccess.B might be logically expected to have functionality related to file access. The .NET Framework uses a hierarchical naming scheme for grouping types into logical categories of related functionality, such as the Microsoft® ASP.NET application framework, or remoting functionality. Design tools can make use of namespaces to make it easier for developers to browse and reference types in their code. The concept of a namespace is not related to that of an assembly. A single assembly may contain types whose hierarchical names have different namespace roots, and a logical namespace root may span multiple assemblies. In the .NET Framework, a namespace is a logical design-time naming convenience, whereas an assembly establishes the name scope for types at run time.

Application Deployment and Isolation

What options are available to deploy my .NET applications?

The .NET Framework simplifies deployment by making zero-impact install and XCOPY deployment of applications feasible. Because all requests are resolved first to the private application directory, simply copying an application's directory files to disk is all that is needed to run the application. No registration is required.

This scenario is particularly compelling for Web applications, Web Services, and self-contained desktop applications. However, there are scenarios where XCOPY is not sufficient as a distribution mechanism. An example is when the application has little private code and relies on the availability of shared assemblies, or when the application is not locally installed (but rather downloaded on demand). For these cases, the .NET Framework provides extensive code download services and integration with the Windows Installer. The code download support provided by the .NET Framework offers several advantages over current platforms, including incremental download, code access security (no more Authenticode dialogs), and application isolation (code downloaded on behalf of one application doesn't affect other applications). The Windows Installer is another powerful deployment mechanism available to .NET applications. All of the features of Windows Installer, including publishing, advertisement, and application repair will be available to .NET applications in Windows Installer 2.0.

I've written an assembly that I want to use in more than one application. Where do I deploy it?

Assemblies that are to be used by multiple applications (for example, shared assemblies) are deployed to the global assembly cache. In the prerelease and Beta builds, use the /i option to the GACUtil SDK tool to install an assembly into the cache:

gacutil /i myDll.dll

Windows Installer 2.0, which ships with Windows XP and Visual Studio .NET will be able to install assemblies into the global assembly cache.

How can I see what assemblies are installed in the global assembly cache?

The .NET Framework ships with a Windows shell extension for viewing the assembly cache. Navigating to % windir%\assembly with the Windows Explorer activates the viewer.

What is an application domain?

An application domain (often AppDomain) is a virtual process that serves to isolate an application. All objects created within the same application scope (in other words, anywhere along the sequence of object activations beginning with the application entry point) are created within the same application domain. Multiple application domains can exist in a single operating system process, making them a lightweight means of application isolation.

An OS process provides isolation by having a distinct memory address space. While this is effective, it is also expensive, and does not scale to the numbers required for large web servers. The Common Language Runtime, on the other hand, enforces application isolation by managing the memory use of code running within the application domain. This ensures that it does not access memory outside the boundaries of the domain. It is important to note that only type-safe code can be managed in this way (the runtime cannot guarantee isolation when unsafe code is loaded in an application domain).

Garbage Collection

What is garbage collection?

Garbage collection is a mechanism that allows the computer to detect when an object can no longer be accessed. It then automatically releases the memory used by that object (as well as calling a clean-up routine, called a "finalizer," which is written by the user). Some garbage collectors, like the one used by .NET, compact memory and therefore decrease your program's working set.

How does non-deterministic garbage collection affect my code?

For most programmers, having a garbage collector (and using garbage collected objects) means that you never have to worry about deallocating memory, or reference counting objects, even if you use sophisticated data structures. It does require some changes in coding style, however, if you typically deallocate system resources (file handles, locks, and so forth) in the same block of code that releases the memory for an object. With a garbage collected object you should provide a method that releases the system resources deterministically (that is, under your program control) and let the garbage collector release the memory when it compacts the working set.

Can I avoid using the garbage collected heap?

All languages that target the runtime allow you to allocate class objects from the garbage-collected heap. This brings benefits in terms of fast allocation, and avoids the need for programmers to work out when they should explicitly 'free' each object.

The CLR also provides what are called ValueTypes—these are like classes, except that ValueType objects are allocated on the runtime stack (rather than the heap), and therefore reclaimed automatically when your code exits the procedure in which they are defined. This is how "structs" in C# operate.

Managed Extensions to C++ lets you choose where class objects are allocated. If declared as managed Classes, with the __gc keyword, then they are allocated from the garbage-collected heap. If they don't include the __gc keyword, they behave like regular C++ objects, allocated from the C++ heap, and freed explicitly with the "free" method.

For additional information about Garbage Collection see:

Garbage Collection: Automatic Memory Management in the Microsoft .NET Framework

Garbage Collection, Part 2: Automatic Memory Management in the Microsoft .NET Framework

Remoting

How do in-process and cross-process communication work in the Common Language Runtime?

There are two aspects to in-process communication: between contexts within a single application domain, or across application domains. Between contexts in the same application domain, proxies are used as an interception mechanism. No marshaling/serialization is involved. When crossing application domains, we do marshaling/serialization using the runtime binary protocol.

Cross-process communication uses a pluggable channel and formatter protocol, each suited to a specific purpose.

If the developer specifies an endpoint using the tool soapsuds.exe to generate a metadata proxy, HTTP channel with SOAP formatter is the default.

If a developer is doing explicit remoting in the managed world, it is necessary to be explicit about what channel and formatter to use. This may be expressed administratively, through configuration files, or with API calls to load specific channels. Options are:

HTTP channel w/ SOAP formatter (HTTP works well on the Internet, or anytime traffic must travel through firewalls)

TCP channel w/ binary formatter (TCP is a higher performance option for local-area networks (LANs))

When making transitions between managed and unmanaged code, the COM infrastructure (specifically, DCOM) is used for remoting. In interim releases of the CLR, this applies also to serviced components (components that use COM+ services). Upon final release, it should be possible to configure any remotable component.

Distributed garbage collection of objects is managed by a system called "leased based lifetime." Each object has a lease time, and when that time expires, the object is disconnected from the remoting infrastructure of the CLR. Objects have a default renew time-the lease is renewed when a successful call is made from the client to the object. The client can also explicitly renew the lease.

Interoperability

Can I use COM objects from a .NET Framework program?

Yes. Any COM component you have deployed today can be used from managed code, and in common cases the adaptation is totally automatic.

Specifically, COM components are accessed from the .NET Framework by use of a runtime callable wrapper (RCW). This wrapper turns the COM interfaces exposed by the COM component into .NET Framework-compatible interfaces. For OLE automation interfaces, the RCW can be generated automatically from a type library. For non-OLE automation interfaces, a developer may write a custom RCW and manually map the types exposed by the COM interface to .NET Framework-compatible types.

Can .NET Framework components be used from a COM program?

Yes. Managed types you build today can be made accessible from COM, and in the common case the configuration is totally automatic. There are certain new features of the managed development environment that are not accessible from COM. For example, static methods and parameterized constructors cannot be used from COM. In general, it is a good idea to decide in advance who the intended user of a given type will be. If the type is to be used from COM, you may be restricted to using those features that are COM accessible.

Depending on the language used to write the managed type, it may or may not be visible by default.

Specifically, .NET Framework components are accessed from COM by using a COM callable wrapper (CCW). This is similar to an RCW (see previous question), but works in the opposite direction. Again, if the .NET Framework development tools cannot automatically generate the wrapper, or if the automatic behavior is not what you want, a custom CCW can be developed.

Can I use the Win32 API from a .NET Framework program?

Yes. Using platform invoke, .NET Framework programs can access native code libraries by means of static DLL entry points.

Here is an example of C# calling the Win32 MessageBox function:

using System;

using System.Runtime.InteropServices;

class MainApp {

[DllImport("user32.dll", EntryPoint="MessageBox")]

public static extern int MessageBox(int hWnd, String strMessage, String strCaption, uint uiType);

public static void Main()

{

MessageBox( 0, "Hello, this is PInvoke in operation!", ".NET", 0 );

}

Testing .aspx Script from Console Prompt

2008-08-26T21:05:00.000-07:00

Platform: Windows NT 4.0 or Windows 2000

Version : VS.NET Beta 2 only

Requirements : Favorite editor (whether SDI or MDI )

Method : Simply write the following code into a file and save it as MyTest.exe , then try this out, perform the following steps:

Copy The MyTest.cs and Test.aspx files to a local directory.
Compile MyTest.exe by typing csc MyTest.cs /r:System.Web.dll within a command prompt in the directory.
Type MyTest.exe Test.aspx

One interesting use of this functionality is to pre-process dynamic ASP.NET requests saving the output as static .htm files that you then prop onto a server. You can do this with MyTest.exe by pipeing the output automatically to a static file. For example:

      MyTest.exe Test.aspx > Test.htm



----------------------------------------------

MyTest.cs

----------------------------------------------



using System ;

using System.IO ;

using System.Web ;

using System.Web.Hosting ;



public class MyExeHost : MarshalByRefObject

public void ProcessRequest ( String page )

HttpRuntime.ProcessRequest ( new SimpleWorkerRequest ( page, null, Console.Out ) ) ;

public static void Main ( String[ ] args )

MyExeHost host = ( MyExeHost )ApplicationHost.CreateApplicationHost ( typeof ( MyExeHost ),

			"/foo", Directory. CurrentDirectory ) ;

foreach ( String page in args )

host.ProcessRequest ( page ) ;

----------------------------------

Test.aspx

----------------------------------

 Hi checking it out ! <%=Now%>

ASP FAQ's 3

2008-07-25T00:43:00.000-07:00

1. What is the result of using Option Explicit?

A. This applies only to Visual Basic, not VBScript.
B. All variables must be dimensioned before use.
C. All variables are dimensioned at run-time.
D. Forces all controls to have a SELECTED
option.
E. Requires all variables be cast as specific datatypes.

2. What should be used in order to determine if the cookie
"FavoriteFlavors" in the request object contains more than one entry?

A. Request.Cookies("FavoriteFlavors").HasItems
B. Request.Cookies("FavoriteFlavors").Collection.Count
C. Request.Cookies("FavoriteFlavors").Dictionary
D. Request.Cookies("FavoriteFlavors").HasKeys
E. Request.Cookies("FavoriteFlavors").Count

3. When is the Session_OnStart event fired?

A. Upon every request from an application by a client for an
.asp document.
B. Upon the first request from an application by a client for
any file in the application.
C. Upon the first request for an .asp document from an
application by a client.
D. Upon the first request for the global.asp file, in which the
event handler is located.
E. Upon the first request for an .htm or .asp document from an
application by client

4. What does Internet Information Server (IIS) assume to be the
default language for Active Server Pages?

A. Jscript
B. JavaScript
C. JAVA
D. VBScript
E. ECMAScript

5. What should the developer use in order to have an Active
Server Page (ASP) invoke a stored procedure on a SQL Server database?

A. ADO
B. RDO
C. RDS
D. OLEDB
E. None of the above.

6. ‘onStart' and 'onEnd' are events of what object(s)?

A. Application only.
B. Session only.
C. Server only.
D. Application and Session only.
E. Application, Session, and Server.

7. What must be installed on an IIS4 machine to use the CDONTS
e-mail server object?

A. FTP service
B. SMTP service
C. IIS administrator
D. Exchange Server
E. IPX/SPX protocol

8. Which line of code would instantiate the Browser
Capabilities component?

A. objBrowser = Server.CreateObject("MSWC.BrowserType")
B. Set objBrowser = Server.CreateObject("MSWC.BrowserType")
C. var objBrowser = Server.CreateObject("MSWC.BrowserType")
D. var objBrowser = CreateObject("MSWC.BrowserType")
E. var objBrowser = Server.CreateObject("BrowserType")

9. What is the Default ScriptTimeOut for Server
Object

A. 20 Sec
B. 30 Sec
C. 60 Sec
D. 90 Sec

10. How many Max Cookies can we Create in
Server

A. 10
B. 20
C. 30
D. 40

11. How Many Types of Cookies
A. 3
B. 2
C. 1
D. 4

12.What is ASP(Active Server Pages)?

ASP is a server side scripting environment for building dynamic and
interactive web pages. Since the scripts run on the server side,
the web server does all the processing.

13. What are the advantages of using ASP?

· Minimizes network traffic by limiting the need for the browser and server
to talk to each other
· Makes for quicker loading time since HTML pages are only downloaded
· Allows to run programs in languages that are not supported by the browser
· Can provide the client with data that does not reside on the client’s
machine
· Provides improved security measures since the script cannot be viewed by
the browser

14. What is HTML(Hypertext Markup Language)?

It’s a method by which web pages can be built and generally used for formatting and linking text.

15. What are the types of HTML?

· Static HTML – Browser uses HTTP to request
HTML file from the Web Server
· Dynamic HTML – Browser uses HTTP to request an executable
application rather than a Static HTML file

16. What is the difference between ASP and HTML? Or Why ASP
is better than HTML?

· ASP executes code on the server side whereas the browser interprets HTML.
· ASP can use any scripting languages
· Gets feedback from the user and return information to the user
· Create pages that will be customized to display only things that will be of
interest to a particular user
· Can edit contents of a web page by updating a text file or a database
rather than the HTML code itself

17. What is a Web Server?

It’s a Computer that provides Web services on the Internet or on a local
Intranet. It is designed to locate, address and send out simple HTML
pages to all other users who access these pages.

18. What is IIS?

IIS is a Web Server that provides Web services, not only for web pages
but also for ftp sites and video and audio services. It integrates
with the database facilities of SQL Server.

19. What do you need to run ASP?

A browser and a Web server.

20. What is a Scripting Language?

It permits to create more interactive Web Pages. Validation, formatting
of web pages can be done. VBScript, JavaScript are some examples.

21. Which is the default Scripting Language of ASP (server-side)?

VBScript

22. Which is the default Scripting Language on the client side?

JavaScript

23. What is Global.asa file?

It is text file that contains details about an ASP application, such as
when it should begin and end.

24. Which is the default Data types in VBScript?

Variant is the default data type in VBScript, which can store a value of any
type.

25. What is the Order of precedence for ARITHMETIC Operators.

^, -(negation), *or /, \, mod, + or –

26. Where will you code OPTION EXPLICIT in an ASP application? WHY?

It should be the first statement before the tag because ASP script is
processed before the HTML statements.

27. What are Constants? How will you declare a constant?

Constants have values that do not change during the execution of the program.
It can be declared using the term CONST. (e.g) Const pi = 3.143

28. What are ARRAYS?

Arrays are variables that store items of similar information.
DIM ARRAY1(4) (declares an array with the name array1 with 5 elements)

29. Arrays can be resized by using the keyword

REDIM

30. What is the maximum size of an array?

Up to 60 dimensions.

ASP OBJECTS

31. Name the ASP Objects?

· Request Object
· Response Object
· Server Object
· Session Object
· Application Object

32. What is Request Object?

Gets information from the user. It has five collections by which values can be accessed. They are:
QueryString, Form, Cookies, Server Variables & ClientCertificate

33. What is Collection?

Collection is a set of name/value pairs where the information supplied by the client is stored.

34. What is application Object?

Shares information among users of an application. Gives a notification when an application starts or ends.

35. What is Application-scope?

Application-scope means that variables (and objects) can be accessed from
any ASP pages that is part of the application.

36. How many global.asa files can an Application have?

Only one global.asa file and it’s placed in the virtual directory’s root.

37. What are the collections of Application Object?

* Contents collection – contains all variables added via scripts in global.asa.
* Static collection – contains the names of all objects added via the
tag in global.asa.

ASP FAQ's 2

2008-07-24T03:09:00.000-07:00

Response.Write a

In the sample code shown above, what will be written to the

screen?

A. 1

B. 2

C. 1, 2

D. 1&2

E. Nothing.

2. <%

Set Application("Thing") =

Server.CreateObject("THINGDOER.thingy")

The above code appears in the global.asa file. What would it

accomplish?

A. It would create a "Thing" object and place it in Contents Collection of

the Application object.

B. It would create a "Thing" object and place it in StaticObjects

Collection of the Application object.

C. It would create a "Thing" object and place it in the Application.Buffer

Collection Of the Application object.

D. It would create an application-level variable named "Thing" with the

value of the object property "THINGDOER.thingy".

E. It would fail to create a "Thing" object because the code requires the

Application.Lock and Application.Unlock methods.

3. <% iPos = Instr("Hello World","r") %>

Referring to the above, what is the value of iPos?

A. 0

B. 1

C. 2

D. 8

E. 9

4. <% varType = rsTest("field1").type %>

In the database table, if the datatype for field1 (shown

above) is Number, what is the value of varType?

A. The field value.

B. A string description.

C. The field name.

D. NULL.

E. An enumerator.

5. What is the program ID (ProgID) for ActiveX Data Objects

in 2-tier and 3-tier database applications?

A. ADO

B. RDODB

C. ADODB

D. RDS

E. OLEDB

6. Which choice is NOT an ADO collection?

A. Properties

B. Records

C. Fields

D. Errors

E. Parameters

7. Which will NOT set the scope of an Active Server Component?

A. Setting the [component name].scope property.

B. Using the Server.CreateObject method.

C. Placing it in the Session or Application OnStart event

handler.

D. Instantiating the component in the global.asa file.

E. Using the tag.

8. How to handle Error in ASP

A. Using On Error Goto

B. Using On Error Resume

C. Using On Error Resume Next

D. Using On Error Goto 0

9. <%

intA = 3

sStrA = "Hello World"

sStrB = "Hello World" + intA

Response.Write sStrB

What would be the result of the above code?

A. Type mismatch error

B. "Hello World, Hello World, Hello World"

C. 0

D. "Hello World 3"

E. "Hello World"

10. What happens when a client submits a form which changes the

value of an Application variable?

A. Client actions cannot change Application variables.

B. The change is not visible to any client until the application is stopped

and started.

C. The change is only visible to future requests made by that

client during their current session.

D. The change is visible to all clients, but only after they

complete their current sessions and begin a new session.

E. The change is visible to all clients immediately after the

form is processed by the server.

11. ADO is an object model for accessing which of the

following?

A. Relational data via Jet.

B. Local or SQL data via Jet.

C. Relational data via ODBC.

D. Non-relational data via DSN-less ODBC.

E. All types of data via OLE DB.

12. Which of the following are Server Object methods ( Choose Two)

A. HTMLEncode,MapPath

B. URLEncode,ScriptTimeout

C. URLEncode,CreateObject

D. ScriptTimeout,Abandon

13. Following is the code Server.MapPath(".") consider the path is

C:\Inetpub\WWWRoot\MAT\Default.asp

What will be the output

A. C:\InetPUb

B. C:\InetPUb\WWWroot

C. C:\InetPUb\wwwroot\MAT

D. Error

14. ClientCertificate is a collection of

A. Server

B. Response

C. Request

D. ObjectContext

15. IsClientConnected is a property of

A. Server

B. Response

C. Request

D. Sesssion

16) What happens to a HTML page?

The browser makes a HTTP request; the server gives a HTTP response to the browser and the browser converts into a HTML page.

17) What happens to ASP pages?

The browser makes a HTTP request; the server does the processing and gives a HTML response to the browser.

18) What are the Web Servers supporting ASP?

· Internet Information Server (IIS) on Windows NT

· Personal Web Server (PWS) on Windows 95

· Peer Web Services on Windows NT

19) Explain the POST & GET Method or Explain the difference between them.

POST METHOD:

The POST method generates a FORM collection, which is sent as a HTTP

request body. All the values typed in the form will be stored in the

FORM collection.

GET METHOD:

The GET method sends information by appending it to the URL(with

a question mark) and stored as a Querystring collection. The

Querystring collection is passed to the server as name/value pair.

The length of the URL should be less than 255 characters.

20) What is the command to display characters to the HTML page?

Response.Write

21) What is a variable?

Variable is a memory location through which the actual values are

stored/retrieved. Its value can be changed.

22) What are LOCAL and GLOBAL variables?

Local variables lifetime ends when the Procedure ends.Global variables

lifetime begins at the start of the script and ends at the end of the

script and it can be used by any procedure within the script. Declaring

a variable by using the keyword PRIVATE makes the variable global within

the script, but if declared using PUBLIC, then the variable can be

referred by all scripts.

23) Naming constraints for a variable.

It can be up to 255 characters

Must start with an alphabet

Must not contain an embedded period or full-stop

24) VBScript is case- insensitive

JavaScript is case sensitive

25) What are the special sub-types in VBScript?

EMPTY: has no value

NULL : Value does not exists (conjunction with database)

OBJECT:

26) What is the Order of precedence for LOGICAL Operators.

NOT, AND, OR, XOR, EQV, IMP

27) What is Response Object?

It controls the information sent to the user. The various methods are:

Response.write – Sends information directly to a browser

Response.Redirect – Directs a user to a URL other than the requested URL

Response.ContentType – Controls the type of content sent

Response.Cookies – Sets cookie values

Response.Buffer – To Buffer information

28) How will you set the values for cookies?

<% Response.Cookies("variable name ")="value" %>.

29) What is the function of Buffer in Response Object?

Buffer controls the HTML output stream manually.

30) What are the methods by which output stream is controlled?

· Flush – sends previous buffered output to the client immediately, but

continues processing the script.

· Clear – erases any already-buffered HTML.

· End – causes the server to stop processing the script.

31) What are the properties used to control the expiration of the page?

· Expires – specifies the number of minutes before a page cached on a browser

expires.

· ExpiresAbsolute – sets the date and time at which a page cached on a browser expires.

32) What are the methods in Application Object?

· Lock – prevents clients from modifying the variables stored in the Application object.

· Unlock – removes the lock from variables stored in the Application object.

33) What are the event handlers of Application Object?

· Application_OnStart – This event will be fired when the first visitor hits the page.

· Application_OnEnd – This event runs when the server is stopped.

34) What is Session Object?

It stores information about a User’s session. Gives a notification when a user session begins or ends.

35) What is a session?

A user accessing an application is known as a session.

36) What are the collections of Session Object?

· Contents collection – contains all the variables established for a session without using the tag.

· Static collection – contains all the objects created with the tag within session scope.

37) What are the properties of Session Object?

· SessionID – returns the session identification number for each user.

· Timeout – sets the timeout period assigned to the Session object for any application, in minutes.

· CodePage – determines the code page that will be used to display content.

· LCID – a locale identifier, which determines time-zone and language, rules for the system.

38) What are the methods in Session Object?

The Session Object has only one method, which is Abandon. It destroys all the objects stored in a Session Object and releases the server resources they occupied.

39) Name some of the ASP components?

· Ad Rotator component – a way to manage advertisements

on the web site.

· Content Linker component – a technique to direct users through a set

of pages on a web site by creating a list of URLs and description of

the next and previous pages.

· Browser Capabilities component – allows to customize the page to the

ability of the browser viewing it.

· Database Access component – allows to access data from the database

40) What are Scripting Objects?

Objects that can enhance the application are known as the Scripting Objects.

41) What are the ASP Scripting Objects?

The Dictionary object, the FileSystemObject object, TextStream object.

42) What is a Dictionary object?

It lets you store and retrieve information in a flexible data

structure. Each value or information stored in a Dictionary is

associated with a key through which the information can be retrieved.

43) What is a FileSystemObject object?

It provides access to the physical file system of the web server.

It gets and manipulates information about all drives in a server,

folders and sub-folders on a drive and files inside a folder.

44) What is Server-Side includes?

It provides extra information by which it makes the site easier to manage.

It can include text files using the #include statement, retrieve the size

and last modification date of a file, defines how variables and error

messages are displayed and inserts the values of HTTP variables in the

page sent back to the browser.

ASP FAQ's 1

2008-07-24T03:08:00.000-07:00

1. <%

strName="John Smith"

Referring to the above, if you want to pass the contents of

the strName variable in a hyperlink, which line of code would you

use?

A. This cannot be done. The anchor is on the client and the

variable is on the server.

B. href="Encode.asp?name=<%=Server.URLPathEncode(strName)%>">click here

C. ">click here

D. ">click here

E. ">click here

2. <%@ Language=VBScript %>

<%If false Then%>

<%Else%>

<%End If%>

What would the above code load?

A. Only the FunctionTwo.inc file into the ASP

page.

B. Both files, since Server Side Includes are processed

before ASP interpreting.

C. Only the FunctionOne.inc file into the ASP page.

D. Neither file, since Server Side Includes are processed

before ASP interpreting.

E. Neither file, since the #INCLUDE statements are commented out.

3. <% Response.Redirect("http://www.sql.com") %>

What does the above code accomplish?

A. It sends the browser the line of sample code, and the browser executes it.

B. It sends the response to "http://www.matsystems.com" instead of to the

Requesting browser.

C. It sends a redirection header back to the browser, and the browser then

requests the new target document.

D. The redirection occurs on the server-side, and the first response the

browser gets is the head and body of the new target document.

E. It causes the server to send a request to the target URL and passes the

response to the requesting browser.

4. How are sessions maintained?

A. The browser sends a cookie to the server with each

request.

B. The browser sends a QueryString variable to the server with

each request.

C. The browser sends a hidden Form variable to the server with

each request.

D. The browser sends a long variable to the server in the BODY

of each request.

E. None of the above.

5. When does the application OnEnd event handler

fire?

A. After every request for an application document, since web servers are

stateless servers.

B. As soon as there are no open connections to any application

document.

C. When the web server is stopped in an orderly fashion.

D. Twenty minutes after the last request for a document in the

application.

E. When there are no application requests for the amount of

time defined by the

SessionTimeout variable.

6. How long is a sessionID guaranteed to be

unique?

A. It is unique for the web server, whether it is restarted or

not.

B. Only until the web server is restarted.

C. It is like a GUID in that it is for any web server at any

time.

D. Only until the session expires, then it can be reissued to

another client.

E. It is unique per client. A client cannot have two sessions

with the same sessionID

7.Which code sample will report whether the client's browser

supports cookies?

A. <% var objFSO = Server.CreateObject("Scripting.FileSystemObject")

response.write objFSO.cookiesSupported

B. You can only use JavaScript for this.

C. <% var objFSO = Server.CreateObject("Scripting.FileSystemObject")

response.write objFSO.cookies

D. <% var objBrowser = Server.CreateObject("MSWC.BrowserType")

response.write objBrowser.cookies

E. <% var objBrowser = Server.CreateObject("MSWC.BrowserType")

response.write objBrowser.cookiesSupported

8. Male

Female

Referring to the above, which line of code would retrieve the

selected radio button value?

A. For cnt=0 to rbSex.count - 1

If rbSex(cnt).value = selected Then

strSex = rbSex(cnt).value

exit for

End If

B. strSex = Request("rbSex").selected.value

C. strSex = Request("rbSex")

D. strSex = Request.rbSex.value

E. For Each value in rbSex

If rbSex.selected = true

strSex = value

exit for

9. The FileSystemObject provides an object interface to drives,

directories, and files for which of the following?

A. Any local or mapped drive on either the server or the

client.

B. Only files and subdirectories in the web site's home

directory.

C. Any local physical drive or mapped drive on the web

server.

D. Any file system physically located on the web server.

E. The client's computer.

10. What purpose is served by the Application.lock

method?

A. It locks the Application object, preventing other clients from altering

any values in the Contents collection.

B. It locks the application, preventing the server from responding to any

requests for application documents.

C. It locks the application, preventing non-SSL requests from

being processed.

D. It locks the Application object, preventing other clients from reading any

values in the Content collection.

E. It locks other clients from reading the Contents

collection.

11. How to Display images using Response

object

A. Contenttype=Application/Brush

B. Contenttype=Image/JPG

C. Contenttype=Application/paint

D. Contenttype=Image/WMF

12.What is the use of following Statement

Response.Expires=120

A.The page will be removed form cache after 120 Hours

B.The page will be removed form cache after 120 Sec

C.The page will be removed form cache before 120 Min

D.The page will be removed form cache after 2 Hours

13. Which choice is NOT a property of Dictionary

Object?

A. Key()

B. CompareMode

C. Item ()

D. Exists ()

E. Count

14. Using VBScript, which of the following Scripting Object(s)

is NOT available from scrrun.dll?

A. TextStream

B. Dictionary Object

C. Err Object

D. FileSystemObject

E. All are available from scrrun.dll.

15. What is an .ASP file?

It is a Text File that contains the combination of the following:

· Text

· HTML tags

· Script Commands

16.How are scripts executed?

ASP provides scripting engines that execute the corresponding

scripting languages on the server side. Scripts should be encoded within the

<% ….%> delimiters.

17. What are the browsers that can access ASP pages?

· Internet Explorer (supports VBScript, JavaScript)

· Netscape Communicator/ Navigator (supports only JavaScript, Vbscript can be also added too)

18. What is a "Virtual Directory"?

Virtual directories are aliases for directory paths on the server.

It allows to move files on the disk between different folders, drives or even

servers without changing the structure of web pages. It avoids typing an extremely

long URL each time to access an ASP page.

19. What is the difference between client-side script and server-side script?

Scripts executed only by the browser without contacting the

server is called client-side script. It is browser dependent. The scripting

code is visible to the user and hence not secure. Scripts executed by the

web server and processed by the server is called server-side script.

20. Give the comment Tags for the following:

VBScript : REM & ‘(apostrophe)

JavaScript : // (single line comment)

/* */ (Multi-line comments)

21.How can you disable the browser to view the code?

Writing codes within the Tag.

22. How does the server identify and execute the server-side scripts within HTML code?

· Including the RUNAT=SERVER attribute in the

Some Limitation or Disadvantage of XML?

XML markup has a few disadvantages:

It can be verbose unless element and attribute names are chosen with care. In large documents the markup overhead need not be large, but in short messages it can be significantly more than the actual data, especially when the element or attribute names are concocted by machine.

Overlapping markup is not permitted (an element cannot start inside one element and end inside another): element markup must nest hierarchically.

How to add in XML document through XSL ?

XSL (the eXtensible Stylesheet Language) is far more sophisticated than CSS. One way to use XSL is to transform XML into HTML before it is displayed by the browser as demonstrated in these examples:

Below is a fraction of the XML file. The second line,

, links the XML file to the XSL file:

Belgian Waffles

$5.95

two of our famous Belgian Waffles

650

How do I convert my existing HTML documents into XML?

Tidy is a command-line utility which runs on a wide variety of operating systems; it uses various command-line switches (parameters) to control its processing. At a minimum, it simply cleans up your HTML by ensuring that elements are properly nested and so on; it also warns you if your HTML uses non-standard code that's likely to cause cross-browser compatibility problems. One of the most useful command-line options is -asxml ("as XML," see?), which does what you seem to be asking. It will properly balance elements, per usual, but it also adds some extra information to the document. For instance, it tacks on an XML declaration, , and a statement, which unambiguously mark this as an XML document. To the root html element it also adds a namespace-declaring attribute that identifies all elements in the document as conforming to the specific XML vocabulary known as XHTML. It even forces all element names to lowercase, since the XHTML standard requires it.

If you're asking about converting HTML to a less generic form of XML than XHTML, your task may turn out to be quite complex. For example, if you've been using HTML to mark up customer invoices, not only the customer's name but also their number, item(s) ordered, quantity, and price are probably all wrapped up inside and
tags. How do you know which "kind of paragraph" contains a given kind of information, so you can turn one instance of the p element into a custname element, another into custnumber, another into price, and so on? If you've been using CSS for styling your HTML, you may have supplied the different p elements with class="custname" (etc.) attributes and so on; if that's the case, you may be able to generate meaningful XML using an XSLT stylesheet. There may also be customized software to do the sort of conversion you want. Otherwise you're probably looking down the barrel of an ugly gun.

What is a schema? What are the limitations of a DTD?

SCHEMA is nothing but METADATA. The schema holds all the information of the xml file that is to be deployed in the project. Metatdata is nothing about data about data since we know that xml is used for data representation language we will be able to understand what metadata is. Metadata includes the tags that is going to be exchanged to and fro from another xml file. DTD (DATA TYPE DEFINITION ) which supervises two conditions namely well formedness and closeness of the xml file. So the user should be aware of what tags he was put into use of this xml file 'A' should be intimated to another application's XML file 'B', by then our xml file will interact with the another xml file, this is the major limitat ion and mandatory issue that the developers should follow.

The difference between asp.net 2003 and asp.net 2005.

2008-07-17T22:57:00.000-07:00

The difference between asp.net 2003 and asp.net 2005.

1. Improving Development productivity by reducing the lines of code to be written by 70%.

2. Increasing performance and scalability for developing fast web applications platforms by providing facilities such as caching.

3. Simplifying the administration and management of web applications

4. Providing enhanced hosting opportunities for Internet Service providers

New Controls:

The final release of ASP.NET includes 40 new controls.

The Grid View control has features for sorting, paging, selection and editing of contents out of the box.

The DetailsView control displays single records in a vertical listing of data. The TreeView control supports the Data Source Provider concept and a number of data sources can be bound to it, including XML data.

The Bulleted list control designed for data binding displays highly configurable HTML lists and provides support for hyperlinks and link buttons.

Apart from the above controls, some other controls have been introduced for the use of image maps, upload of files and rapid implementation of Wizards.

Master Pages:

Master pages have been designed to help web developers design templates with place holders for content.

Site Navigation:

Implementation of navigation has been made simple with the integrated navigation structure based on XML data.

User Management::

User management system is provided by providing special controls for registration, login and so on with data providers to handle the data storage without any code.

Themes and Skins:

This allows developers define themes and skins for their applications. The Implementation of themes provides for design properties, CSS support and integration of individual graphics.

Site Counters:

This feature helps in counting page requests and also clicks of controls. The .NET framework provides an extensive API to analyze, visualize and process the data.

Deployment:

ASP.NET 2.0 opens up several new possibilities for the deployment of the applications. Developers can now create or open projects using the file system or the local IIS, FrontPage Extensions (FTP). The new functionality for compiling complete web applications includes copying of Dynamic link Libraries(DLLs) to the Web server.

The new features of ASP.NET, simplify the overall programming model.

The compiler is designed to generate most of the code and the developer is freed

from repetitive programming tasks.

Difference between VB6 and VB.NET:

VB6 uses the VB-Runtime while VB.NET uses the .Net CLR. The CLR uses better code translation through Just in Time compiler while VB-Runtime interprets the code.
VB6 was interpreter based language while VB.NET is a compiled language.
VB6 was not a type-safe language while VB.NET is a type safe language.
VB6 used ‘On Error Goto’ syntax to handle exceptions at runtime. VB.NET uses the Try…Catch…Finally syntax to handle exceptions at runtime.

VB.NET has much enhanced object oriented support than VB6.
VB6 does not allow developing the multithreaded applications. In VB.NET you can create multithreaded applications.
VB6 was only considered for desktop windows application. In VB.NET you can also develop web applications, distributed applications.

VB.NET is platform independent because of .Net framework. Programs written in VB.NET can run on any platform where .Net framework is present.
VB.NET also supports language interoperability. VB6 provides this functionality through COM but it was limited and difficult to use and manage. VB.Net makes it easier because of the presence of Intermediate Language (IL) and Common Language Specification (CLS) of the .NET architecture.

VB6 uses COM (Component Object Model) as component architecture. VB.NET uses assemblies as its component architecture. The Assemblies architecture has removed a lot of problems with COM including DLL-Hell and versioning problem.
Components created in VB6 (COM) need to make and update registry entries. VB.NET does not require any registry entry making the deployment easier.
VB6 used ADODB and record-sets to implement data access applications. VB.NET uses ADO.NET and datasets to build data access applications. The ADO.NET also supports the disconnected data access.

STATE MANAGEMENT

2008-07-12T08:00:00.001-07:00

What is ViewState?

ViewState allows the state of objects (serializable) to be stored in a hidden field on the page. ViewState is transported to the client and back to the server, and is not stored on the server or any other external source. ViewState is used the retain the state of server-side objects between postabacks.

Why should we have to move from inproc session to outproc session

I was using Inprocess session objects, but incase of aspnet process crashes the session objects were lost as a result I decided to shift to out of porocess session objects. For this i had to serialize the objects. While doing that I made the classes serializable whose objects I store in sessions. However, when I run the application I get the following error.

Unable to serialize the session state. Please note that non-serializable objects or MarshalByRef objects are not permitted when session state mode is 'StateServer' or 'SQLServer'. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Web.HttpException: Unable to serialize the session state. Please note that non-serializable objects or MarshalByRef objects are not permitted when session state mode is 'StateServer' or
'SQLServer'.

What is the lifespan for items stored in ViewState?

Item stored in ViewState exist for the life of the current page. This includes postbacks (to the same page).

What does the "EnableViewState" property do? Why would I want it on or off?

It allows the page to save the users input on a form across postbacks. It saves the server-side values for a given control into ViewState, which is stored as a hidden value on the page before sending the page to the clients browser. When the page is posted back to the server the server control is recreated with the state stored in viewstate.

What are the different types of Session state management options available with ASP.NET?

ASP.NET provides In-Process and Out-of-Process state management. In-Process stores the session in memory on the web server. This requires the a "sticky-server" (or no load-balancing) so that the user is always reconnected to the same web server. Out-of-Process Session state management stores data in an external data source. The external data source may be either a SQL Server or a State Server service. Out-of-Process state management requires that all objects stored in session are serializable.

Application and Session Events

The ASP.NET page framework provides ways for you to work with events that can be raised when your application starts or stops or when an individual user's session starts or stops:

• Application events are raised for all requests to an application. For example, Application_BeginRequest is raised when any Web Forms page or XML Web service in your application is requested. This event allows you to initialize resources that will be used for each request to the application. A corresponding event, Application_EndRequest, provides you with an opportunity to close or otherwise dispose of resources used for the request.

• Session events are similar to application events (there is a Session_OnStart and a Session_OnEnd event), but are raised with each unique session within the application. A session begins when a user requests a page for the first time from your application and ends either when your application explicitly closes the session or when the session times out.
You can create handlers for these types of events in the Global.asax file.

Difference between ASP Session and ASP.NET Session?

asp.net session supports cookie less session & it can span across multiple servers.

What is cookie less session? How it works?

By default, ASP.NET will store the session state in the same process that processes the request, just as ASP does. If cookies are not available, a session can be tracked by adding a session identifier to the URL. This can be enabled by setting the following:

http://samples.gotdotnet.com/quickstart/aspplus/doc/stateoverview.aspx

How you will handle session when deploying application in more than a server? Describe session handling in a webfarm, how does it work and what are the limits?

By default, ASP.NET will store the session state in the same process that processes the request, just as ASP does. Additionally, ASP.NET can store session data in an external process, which can even reside on another machine. To enable this feature:

• Start the ASP.NET state service, either using the Services snap-in or by executing "net start aspnet_state" on the command line. The state service will by default listen on port 42424. To change the port, modify the registry key for the service: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\aspnet_state\Parameters\Port
• Set the mode attribute of the section to "StateServer".
• Configure the stateConnectionString attribute with the values of the machine on which you started aspnet_state.
The following sample assumes that the state service is running on the same machine as the Web server ("localhost") and uses the default port (42424):

Note that if you try the sample above with this setting, you can reset the Web server (enter iisreset on the command line) and the session state value will persist.
**
What method do you use to explicitly kill a users session?

Abandon()

What are the different ways you would consider sending data across pages in ASP (i.e between 1.asp to 2.asp)?

Session
public properties

ASP.NET supports three modes of session state:

• InProc: In-Proc mode stores values in the memory of the ASP.NET worker process. Thus, this mode offers the fastest access to these values. However, when the ASP.NET worker process recycles, the state data is lost.

• StateServer: Alternately, StateServer mode uses a stand-alone Microsoft Windows service to store session variables. Because this service is independent of Microsoft Internet Information Server (IIS), it can run on a separate server. You can use this mode for a load-balancing solution because multiple Web servers can share session variables. Although session variables are not lost if you restart IIS, performance is impacted when you cross process boundaries.

• SqlServer: If you are greatly concerned about the persistence of session information, you can use SqlServer mode to leverage Microsoft SQL Server to ensure the highest level of reliability. SqlServer mode is similar to out-of-process mode, except that the session data is maintained in a SQL Server. SqlServer mode also enables you to utilize a state store that is located out of the IIS process and that can be located on the local computer or a remote server.

What is State Management in .Net and how many ways are there to maintain a state in .Net? What is view state?

Web pages are recreated each time the page is posted to the server. In traditional Web programming, this would ordinarily mean that all information associated with the page and the controls on the page would be lost with each round trip.
To overcome this inherent limitation of traditional Web programming, the ASP.NET page framework includes various options to help you preserve changes — that is, for managing state. The page framework includes a facility called view state that automatically preserves property values of the page and all the controls on it between round trips.
However, you will probably also have application-specific values that you want to preserve. To do so, you can use one of the state management options.
Client-Based State Management Options:
View State
Hidden Form Fields
Cookies
Query Strings
Server-Based State Management Options
Application State
Session State
Database Support

What are the disadvantages of view state / what are the benefits?

Automatic view-state management is a feature of server controls that enables them to repopulate their property values on a round trip (without you having to write any code). This feature does impact performance, however, since a server control's view state is passed to and from the server in a hidden form field. You should be aware of when view state helps you and when it hinders your page's performance.

When maintaining session through Sql server, what is the impact of Read and Write operation on Session objects? will performance degrade?

Maintaining state using database technology is a common practice when storing user-specific information where the information store is large. Database storage is particularly useful for maintaining long-term state or state that must be preserved even if the server must be restarted.
**

What are the contents of cookie?
**

How do you create a permanent cookie?
**

What is ViewState? What does the "EnableViewState" property do? Why would I want it on or off?
**

Explain the differences between Server-side and Client-side code?

Server side code will process at server side & it will send the result to client. Client side code (javascript) will execute only at client side.

Can you give an example of what might be best suited to place in the Application_Start and Session_Start subroutines?
**

Which ASP.NET configuration options are supported in the ASP.NET implementation on the shared web hosting platform?

A: Many of the ASP.NET configuration options are not configurable at the site, application or subdirectory level on the shared hosting platform. Certain options can affect the security, performance and stability of the server and, therefore cannot be changed. The following settings are the only ones that can be changed in your site’s web.config file (s):
browserCaps
clientTarget
pages
customErrors
globalization
authorization
authentication
webControls
webServices
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpguide/html/cpconaspnetconfiguration.asp

Briefly describe the role of global.asax?

How can u debug your .net application?

How do u deploy your asp.net application?

Where do we store our connection string in asp.net application?

Various steps taken to optimize a web based application (caching, stored procedure etc.)

How does ASP.NET framework maps client side events to Server side events.

Caching Options in ASP.NET

ASP.NET supports three types of caching for Web-based applications:

Page Level Caching (called Output Caching)
Page Fragment Caching (often called Partial-Page Output Caching)
Programmatic or Data Caching

We'll look at each of these options, including how, and when, to use each option to increase your site's performance!

Output Caching

Page level, or output caching, caches the HTML output of dynamic requests to ASP.NET Web pages. The way ASP.NET implements this (roughly) is through an Output Cache engine. Each time an incoming ASP.NET page request comes in, this engine checks to see if the page being requested has a cached output entry. If it does, this cached HTML is sent as a response; otherwise, the page is dynamically rendered, it's output is stored in the Output Cache engine.

Output Caching is particularly useful when you have very static pages. For example, the articles here on 4GuysFromRolla.com are very static. The only dynamic content is the banners, the dynamic selection being performed on a separate ad server. Hence, the articles on 4Guys would be prime candidates for Output Caching.

Output caching is easy to implement. By simply using the @OuputCache page directive, ASP.NET Web pages can take advantage of this powerful technique. The syntax looks like this:

<%@OutputCache Duration="60" VaryByParam="none" %>
[See a live demo!]

The Duration parameter specifies how long, in seconds, the HTML output of the Web page should be held in the cache. When the duration expires, the cache becomes invalid and, with the next visit, the cached content is flushed, the ASP.NET Web page's HTML dynamically generated, and the cache repopulated with this HTML. The VaryByParam parameter is used to indicate whether any GET (QueryString) or POST (via a form submit with method="POST") parameters should be used in varying what gets cached. In other words, multiple versions of a page can be cached if the output used to generate the page is different for different values passed in via either a GET or POST.

The VaryByParam is a useful setting that can be used to cache different "views" of a dynamic page whose content is generated by GET or POST values. For example, you may have an ASP.NET Web page that reads in a Part number from the QueryString and displays information about a particular widget whose part number matches the QueryString Part number. Imagine for a moment that Output Caching ignored the QueryString parameters altogether (which you can do by setting VaryByParam="none"). If the first user visited the page with QueryString /ProductInfo.aspx?PartNo=4, she would see information out widget #4. The HTML for this page would be cached. The next user now visits and wished to see information on widget #8, a la /ProductInfo.aspx?PartNo=8. If VaryByParam is set to VaryByParam="none", the Output Caching engine will assume that the requests to the two pages are synonymous, and return the cached HTML for widget #4 to the person wishing to see widget #8! To solve for this problem, you can specify that the Output Caching engine should vary its caches based on the PartNo parameter by either specifying it explicitly, like VaryByParam="PartNo", or by saying to vary on all GET/POST parameters, like: VaryByParam="*".

Partial-Page Output Caching

More often than not, it is impractical to cache entire pages. For example, you may have some content on your page that is fairly static, such as a listing of current inventory, but you may have other information, such as the user's shopping cart, or the current stock price of the company, that you wish to not be cached at all. Since Output Caching caches the HTML of the entire ASP.NET Web page, clearly Output Caching cannot be used for these scenarios: enter Partial-Page Output Caching.

Partial-Page Output Caching, or page fragment caching, allows specific regions of pages to be cached. ASP.NET provides a way to take advantage of this powerful technique, requiring that the part(s) of the page you wish to have cached appear in a User Control. One way to specify that the contents of a User Control should be cached is to supply an OutputCache directive at the top of the User Control. That's it! The content inside the User Control will now be cached for the specified period, while the ASP.NET Web page that contains the User Control will continue to serve dynamic content. (Note that for this you should not place an OutputCache directive in the ASP.NET Web page that contains the User Control - just inside of the User Control.)

Now that we've tackled Output Caching and Fragment Caching, there is still one more caching technique worth discussing: Data Caching. In Part 2 we'll examine what, exactly, Data Caching is and how you can use it to improve the performance of your ASP.NET Web pages. We'll also examine a really cool, real-world caching demo!
In Part 1 we looked at how to use Output Caching and Fragement Caching of an ASP.NET Web page. These two techniques cached either the full HTML output of an ASP.NET Web page, or a portion of the HTML output of an ASP.NET Web page (by caching the HTML output of a User Control). In this part, we'll examine Data Caching, which is an in-memory cache used for caching objects.

Data Caching

Sometimes, more control over what gets cached is desired. ASP.NET provides this power and flexibility by providing a cache engine. Programmatic or data caching takes advantage of the .NET Runtime cache engine to store any data or object between responses. That is, you can store objects into a cache, similar to the storing of objects in Application scope in classic ASP. (As with classic ASP, do not store open database connections in the cache!)

Realize that this data cache is kept in memory and "lives" as long as the host application does. In other words, when the ASP.NET application using data caching is restarted, the cache is destroyed and recreated. Data Caching is almost as easy to use as Output Caching or Fragment caching: you simply interact with it as you would any simple dictionary object. To store a value in the cache, use syntax like this:

Cache["foo"] = bar; // C#
Cache("foo") = bar ' VB.NET

To retrieve a value, simply reverse the syntax like this:

bar = Cache["foo"]; // C#
bar = Cache("foo") ' VB.NET

Note that after you retrieve a cache value in the above manner you should first verify that the cache value is not null prior to doing something with the data. Since Data Caching uses an in-memory cache, there are times when cache elements may need to be evicted. That is, if there is not enough memory and you attempt to insert something new into the cache, something else has gotta go! The Data Cache engine does all of this scavenging for your behind the scenes, of course. However, don't forget that you should always check to ensure that the cache value is there before using it. This is fairly simply to do - just check to ensure that the value isn't null/Nothing. If it is, then you need to dynamically retrieve the object and restore it into the cache.

For example, if we were storing a string myString in the cache whose value was set from some method named SetStringToSomething(), and we wanted to read the value of myString from the cache, we'd want to:

Read the myString from the cache: str = Cache("myString")
Ensure that str wasn't null/Nothing. If it was, we'd want to get the value of str from SetStringToSomething(), and then put it in the cache, like so:
'Try to read the cache entry MyString into str
str = Cache("myString")

'Check if str is Nothing
If str is Nothing then
'If it is, populate str from SetStringToSomething()
str = SetStringToSomething()

'Now insert str into the cache entry myString
Cache("myString") = str
End If

Besides using the dictionary-like key/value assignment, as shown in the example above, you can also use the Insert or Add method to add items to the cache. Both of these methods are overloaded to accommodate a variety of situations. The Add and the Insert methods operate exactly the same except the Add method returns a reference to the object being inserted to the cache. Because of the similarity of the two methods, I will concentrate on the Insert method. Note that the Insert method allows you to simply add items to the cache using a key and value notation as well. For example to simply add an instance of the object bar to the cache named foo, use syntax like this:

Cache.Insert("foo", bar); // C#
Cache.Insert("foo", bar) ' VB.NET

(Note that this is synonymous to using the Cache("foo") = bar syntax we looked at earlier.)

Note that with inserting items into the Data Cache using the Cache(key) = value method or the Cache.Insert(key, value) we have no control over when (if ever) the items are evicted from the cache. However, there are times when we'd like to have control over when items leave the cache. For example, perhaps we want to have an inserted item in the cache to only live for n seconds, as with Output Caching. Or perhaps we'd like to have it exit the cache n seconds after it's last accessed. With Data Caching, you can optionally specify when the cache should have a member evicted.

Additionally, you can have an item evicted from the cache when a file changes. Such an eviction dependency is called a file dependency, and has many real-world applications, especially when working with XML files. For example, if you want to pull data out of an XML file, but you don't want to constantly go to disk to read the data, you can tell the ASP.NET caching engine to expire the cached XML file whenever the XML file on disk is changed. To do this, use the following syntax:

Cache.Insert("foo", bar, new CacheDependancy(Server.MapPath("BarData.xml")))

By using this syntax, the cache engine takes care of removing the object bar from the cache when BarData.xml file is changed. Very cool! There are also means to have the inserted cache value expire based on an interval, or at an absolute time, as discussed before. For more information on these methods, consult the documentation for the Cache.Insert method.