Page.RegisterRequiresPostBack Method (Control)


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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 void RegisterRequiresPostBack(
	Control control


Type: System.Web.UI.Control

The control to be registered.

Exception Condition

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 Forms 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.

System_CAPS_security Security 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.

protected void Text_Change(object sender, EventArgs e)
  myLabel.Text = "<b>Welcome " + myTextBox.Text + " to ASP.NET</b>";

protected void Page_PreRender(object sender, EventArgs e)

.NET Framework
Available since 1.1
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