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Page.SetFocus Method

  • Reference

Definition

Namespace:
System.Web.UI
Assembly:
System.Web.dll

Sets the browser focus to the specified control.

Overloads

SetFocus(Control)

Sets the browser focus to the specified control.
SetFocus(String)

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

SetFocus(Control)

Sets the browser focus to the specified control.

public:
 void SetFocus(System::Web::UI::Control ^ control);
public void SetFocus (System.Web.UI.Control control);
member this.SetFocus : System.Web.UI.Control -> unit
Public Sub SetFocus (control As Control)

Parameters

control
Control

The control to receive focus.

Exceptions

ArgumentNullException

control is null.

InvalidOperationException

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

-or-

SetFocus(Control) is called after the PreRender event.

Examples

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

Important

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);
    }
</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>

<%@ 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)
    End Sub
</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>

Remarks

Use the SetFocus method to make the specified control the active control on 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.

Applies to

SetFocus(String)

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

public:
 void SetFocus(System::String ^ clientID);
public void SetFocus (string clientID);
member this.SetFocus : string -> unit
Public Sub SetFocus (clientID As String)

Parameters

clientID
String

The ID of the control to set focus to.

Exceptions

ArgumentNullException

clientID is null.

InvalidOperationException

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

-or-

SetFocus(String) is called after the PreRender event.

Examples

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

Important

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>

<%@ 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 xmlns="http://www.w3.org/1999/xhtml" >
<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>

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.

Applies to