Page.SetFocus Method (String)
Sets the browser focus to the control with the specified identifier.
Assembly: System.Web (in System.Web.dll)
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| ArgumentNullException |
clientID is Nothing. |
| InvalidOperationException |
SetFocus is called when the control is not part of a Web Forms page. - or - |
Use the SetFocus method to make the control with the specified ID string the active control in the Web page displayed by the browser. The SetFocus method must be called before the page is prepared for rendering to the client in the PreRender event.
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Note
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The SetFocus method will work only on browsers supporting ECMAScript version 1.3 or later. |
The following code example sets the focus to the second text box on a Web page.
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Security Note
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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. |
<%@ page language="C#" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script runat="server"> void Page_Init(object sender, EventArgs e) { SetFocus(focusHere.ClientID); } </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head id="Head1" runat="server"> <title>Untitled Page</title> </head> <body> <form id="form1" runat="server"> <asp:textbox id="default" runat="server" /><br /> <asp:textbox id="focusHere" runat="server" /> </form> </body> </html>
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
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.