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Page.RegisterRequiresPostBack Method

Registers a control as one that requires postback handling when the page is posted back to the server.

Namespace:  System.Web.UI
Assembly:  System.Web (in System.Web.dll)

Public Sub RegisterRequiresPostBack ( _
	control As Control _
Dim instance As Page 
Dim control As Control



Type: System.Web.UI.Control

The control to be registered.


The control to register does not implement the IPostBackDataHandler interface.

The control to be registered must implement the IPostBackDataHandler interface or an HttpException is raised. When implemented by a control, the IPostBackDataHandler interface enables handling of post back data and raising of any post back data changed events. For more information on the server control event model, see ASP.NET Web Server Control Event Model.

Register controls with the page at or before the Page_PreRender event of the page life cycle.

The following code example uses the RegisterRequiresPostBack method to require a text box control, myTextBox, to be posted back before any code associated with the text box can execute. TextBox controls implement the IPostBackDataHandler interface.

Security noteSecurity Note:

This example has a text box that accepts user input, which is a potential security threat. By default, ASP.NET Web pages validate that user input does not include script or HTML elements. For more information, see Script Exploits Overview.

Sub Text_Change(ByVal sender As Object, ByVal e As EventArgs)
  myLabel.Text = "<b>Welcome " + myTextBox.Text + " to ASP.NET</b>" 
End Sub 'Text_Change

Protected Sub Page_PreRender(ByVal sender As Object, ByVal e As System.EventArgs)
End Sub

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0