TextBox.TextChanged Event

public event EventHandler TextChanged

<asp:TextBox OnTextChanged="EventHandler" />

Implements

The TextChanged event is raised when the content of the text box changes between posts to the server.

Note
A TextBox control must persist some values between posts to the server for this event to work correctly. Be sure that view state is enabled for this control.

For more information about handling events, see Consuming Events.

The following example shows how you can use this event to respond to changes in the TextBox control. The code displays the contents of the Text property of the control in a label when the when the Text property is changed. User input in a Web Forms page can include potentially malicious client script. By default, the Web Forms page validates that user input does not include script or HTML elements. For more information, see How to: Protect Against Script Exploits in a Web Application by Applying HTML Encoding to Strings.

protected void TextBox1_TextChanged(object sender, EventArgs e)
{
   Label1.Text = Server.HtmlEncode(TextBox1.Text);
}

.NET Framework

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

Other Resources