WebControl.TabIndex Property
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Gets or sets the tab index of the Web server control.
public:
virtual property short TabIndex { short get(); void set(short value); };public virtual short TabIndex { get; set; }member this.TabIndex : int16 with get, setPublic Overridable Property TabIndex As ShortProperty Value
The tab index of the Web server control. The default is 0, which indicates that this property is not set.
Exceptions
The specified tab index is not between -32768 and 32767.
Examples
The following example illustrates how to use the TabIndex property of the WebControl to set the tab order of controls on the page.
Note
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.
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 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>
Remarks
Use the TabIndex 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 TabIndex 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 TabIndex 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.
Note
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 TabIndex property to a negative value.
Note
This property is supported only in Internet Explorer 4 and later.
