How can I upload a file from my ASP.NET page?

In order to perform file upload in your ASP.NET page, you will need to use two classes: the System.Web.UI.HtmlControls.HtmlInputFile class and the System.Web.HttpPostedFile class. The HtmlInputFile class represents and HTML input control that the user will use on the client side to select a file to upload. The HttpPostedFile class represents the uploaded file and is obtained from the PostedFile property of the HtmlInputFile class. In order to use the HtmlInputFile control, you need to add the enctype attribute to your form tag as follows:

Also, remember that the /data directory is the only directory with Write permissions enabled for the anonymous user. Therefore, you will need to make sure that the your code uploads the file to the /data directory or one of its subdirectories.
Below is a simple example of how to upload a file via an ASP.NET page in C# and VB.NET.
C#
<%@ Import Namespace="System" %>
<%@ Import Namespace="System.Web" %>
<%@ Import Namespace="System.Web.UI.HtmlControls" %>
<%@ Import Namespace="System.IO" %>
<%@ Import Namespace="System.Drawing" %>

uploaded

bytes