Gets or sets the tab index of the Web server control.

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

Syntax
public virtual short TabIndex { get; set; }
public:
property short TabIndex {
	virtual short get();
	virtual void set(short value);
}
abstract TabIndex : int16 with get, set
override TabIndex : int16 with get, set
Public Overridable Property TabIndex As Short

Property Value

Type:

The tab index of the Web server control. The default is 0, which indicates that this property is not set.

Exceptions
Exception Condition
ArgumentOutOfRangeException

The specified tab index is not between -32768 and 32767.

Remarks

Use the property to specify or determine the tab index of a Web server control on the Web Forms page. When you press the Tab key, the order in which the Web server controls receive focus is determined by the property of each control. When a page is initially loaded, the first item that receives focus when the Tab key is pressed is the address bar. Next, the controls on the Web Forms page are tabbed to in ascending order, based on the value of the property of each control, starting with the smallest positive, nonzero value. If multiple controls share the same tab index, the controls will receive focus in the order they are declared on the Web Forms page. Finally, controls that have a tab index of zero are tabbed to in the order they are declared.

System_CAPS_noteNote

Only controls with a nonzero tab index will render the tabindex attribute.

You can remove a Web Server control from the tab order by setting the property to a negative value.

System_CAPS_noteNote

This property is supported only in Internet Explorer 4 and later.

Examples

The following example illustrates how to use the property of the WebControl to set the tab order of controls on the page.

System_CAPS_noteNote

The following code sample uses the single-file code model and may not work correctly if copied directly into a code-behind file. This code sample must be copied into an empty text file that has an .aspx extension. For more information on the Web Forms code model, see ASP.NET Web Forms Page Code Model.

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.

<%@ 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 SubmitBtn1_Click(Object sender, EventArgs e)
    {
        SubmitBtn1.TabIndex = 0;
        TextBox1.TabIndex = (short)((TextBox1.Text=="") ? 0 : 
            System.Int32.Parse(TextBox1.Text));
        TextBox2.TabIndex = (short)((TextBox2.Text=="") ? 0 : 
            System.Int32.Parse(TextBox2.Text));
        TextBox3.TabIndex = (short)((TextBox3.Text=="") ? 0 : 
            System.Int32.Parse(TextBox3.Text));
    }

</script>


<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head2" runat="server">
    <title>Enabled Property Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>

    <h3>TabIndex Property of a Web Control<br /></h3>

    <p>
        Enter a number (1, 2, or 3) in each text box, <br /> 
        click the Submit button to set the TabIndexes, then <br /> 
        click on the page and tab through the page to verify.
    </p>

    <p><asp:Button id="SubmitBtn1" OnClick="SubmitBtn1_Click" 
            Text="Submit" runat="server"/>
    </p>

    <p><asp:TextBox id="TextBox1" BackColor="Pink" 
            runat="server"/>
    </p>
    <p><asp:TextBox id="TextBox2" BackColor="LightBlue" 
            runat="server"/>
    </p>
    <p><asp:TextBox id="TextBox3" BackColor="LightGreen" 
            runat="server"/>
    </p>  

    </div>
    </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 SubmitBtn1_Click(sender As Object, e As EventArgs)
        SubmitBtn1.TabIndex = 0
        If TextBox1.Text = "" Then
            TextBox1.TabIndex = 0
        Else
            TextBox1.TabIndex = System.Int16.Parse(TextBox1.Text)
        End If
        If TextBox2.Text = "" Then
            TextBox2.TabIndex = 0
        Else
            TextBox2.TabIndex = System.Int16.Parse(TextBox2.Text)
        End If
        If TextBox3.Text = "" Then
            TextBox3.TabIndex = 0
        Else
            TextBox3.TabIndex = System.Int16.Parse(TextBox3.Text)
        End If
    End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head2" runat="server">
    <title>Enabled Property Example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>

    <h3>TabIndex Property of a Web Control<br /></h3>

    <p>
        Enter a number (1, 2, or 3) in each text box, <br /> 
        click the Submit button to set the TabIndexes, then <br /> 
        click on the page and tab through the page to verify.
    </p>

    <asp:Button id="SubmitBtn1" OnClick="SubmitBtn1_Click" 
        Text="Submit" runat="server"/>
    <p>
        <asp:TextBox id="TextBox1" BackColor="Pink" 
            runat="server"/>
    </p>
    <p>
        <asp:TextBox id="TextBox2" BackColor="LightBlue" 
            runat="server"/>
    </p>
    <p>
        <asp:TextBox id="TextBox3" BackColor="LightGreen" 
            runat="server"/>
    </p>  

    </div>
    </form>
</body>
</html>
Version Information
.NET Framework
Available since 1.1
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