body { font-family: Arial, sans-serif; line-height: 1.6; margin: 0; padding: 0; color: #333; } .container { max-width: 1200px; margin: 0 auto; padding: 20px; } h1, h2, h3 { color: #2c3e50; } h1 { border-bottom: 2px solid #3498db; padding-bottom: 10px; } h2 { margin-top: 30px; } .code-block { background-color: #f8f9fa; border: 1px solid #ddd; border-radius: 4px; padding: 15px; margin: 20px 0; overflow-x: auto; font-family: 'Courier New', monospace; } .note { background-color: #e7f3fe; border-left: 4px solid #2196F3; padding: 12px; margin: 20px 0; } .example-link { display: inline-block; background-color: #4CAF50; color: white; padding: 8px 16px; text-decoration: none; border-radius: 4px; margin-top: 10px; } .example-link:hover { background-color: #45a049; } .navigation { background-color: #f5f5f5; padding: 15px; margin-bottom: 30px; border-radius: 4px; } .navigation ul { list-style-type: none; padding: 0; } .navigation li { margin: 5px 0; } .navigation a { text-decoration: none; color: #3498db; } .navigation a:hover { text-decoration: underline; } .property-table { width: 100%; border-collapse: collapse; margin: 20px 0; } .property-table th, .property-table td { border: 1px solid #ddd; padding: 12px; text-align: left; } .property-table th { background-color: #f2f2f2; } .footer { margin-top: 50px; padding-top: 20px; border-top: 1px solid #eee; text-align: center; color: #777; }

ASP.NET SelectedIndex Property

Definition and Usage

The SelectedIndex property represents the ordinal index of the selected item in the list.

Example

The following example gets the index of a ListItem in a RadioButtonList control:

<script runat="server">

Sub Change(obj As Object, e As EventArgs)
    Response.Write("Selected index: " & rb1.SelectedIndex)
End Sub

</script>

<form runat=server>

<asp:RadioButtonList id="rb1" AutoPostBack="true"
    runat="server" OnSelectedIndexChanged="Change">
    <asp:ListItem Text="Item 1" />
    <asp:ListItem Text="Item 2" />
</asp:RadioButtonList>

</form>

Try it yourself »

More Examples

This property is commonly used with controls that inherit from ListControl, such as:

ListBox
DropDownList
RadioButtonList
BulletedList

Note: The index is zero-based. If no item is selected, the SelectedIndex property returns -1.

Property Values

Value	Description
Integer	The zero-based index of the selected item. Default is 0 (first item selected).

Related Properties

SelectedItem - Gets the selected item object
Items - Gets the collection of items in the list
SelectedValue - Gets the value of the selected item

YouTip

Prop Webcontrol Listcontrol Selectedindex