Page.SetFocus Method (String) (System.Web.UI)

SetFocus Method (String)

.NET Framework Class Library

Page..::.SetFocus Method (String)

Sets the browser focus to the control with the specified identifier.

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

Syntax

Visual Basic (Declaration)

Public Sub SetFocus ( _
    clientID As String _
)

Visual Basic (Usage)

Dim instance As Page
Dim clientID As String

instance.SetFocus(clientID)

public void SetFocus(
    string clientID
)

Visual C++

public:
void SetFocus(
    String^ clientID
)

JScript

public function SetFocus(
    clientID : String
)

Parameters

clientID: Type: System..::.String
The ID of the control to set focus to.

Exceptions

Exception	Condition
ArgumentNullException	clientID is nullNothingnullptra null reference (Nothing in Visual Basic).
InvalidOperationException	SetFocus is called when the control is not part of a Web Forms page. - or - SetFocus is called after the PreRender event.

Exception

Condition

ArgumentNullException

clientID is nullNothingnullptra null reference (Nothing in Visual Basic).

InvalidOperationException

SetFocus is called when the control is not part of a Web Forms page.

- or -

SetFocus is called after the PreRender event.

Remarks

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.

Note:
The SetFocus method will work only on browsers supporting ECMAScript version 1.3 or later.

Examples

The following code example sets the focus to the second text box on a Web page.

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.

Visual Basic

<%@ page language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
    Sub Page_Init(ByVal sender As Object, ByVal e As EventArgs)
        SetFocus(focusHere.ClientID)
    End Sub
</script>

<html  >
<head 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>

<%@ 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  >
<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>

Platforms

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.

Version Information

.NET Framework

Supported in: 3.5, 3.0, 2.0

Reference

Page Class

Page Members

SetFocus Overload

System.Web.UI Namespace

MaintainScrollPositionOnPostback()()()