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ListBox Web Server Control Declarative Syntax 

Creates a single-selection or multiselection list box.

<asp:ListBox
    AccessKey="string"
    AppendDataBoundItems="True|False"
    AutoPostBack="True|False"
    BackColor="color name|#dddddd"
    BorderColor="color name|#dddddd"
    BorderStyle="NotSet|None|Dotted|Dashed|Solid|Double|Groove|Ridge|
        Inset|Outset"
    BorderWidth="size"
    CausesValidation="True|False"
    CssClass="string"
    DataMember="string"
    DataSource="string"
    DataSourceID="string"
    DataTextField="string"
    DataTextFormatString="string"
    DataValueField="string"
    Enabled="True|False"
    EnableTheming="True|False"
    EnableViewState="True|False"
    Font-Bold="True|False"
    Font-Italic="True|False"
    Font-Names="string"
    Font-Overline="True|False"
    Font-Size="string|Smaller|Larger|XX-Small|X-Small|Small|Medium|
        Large|X-Large|XX-Large"
    Font-Strikeout="True|False"
    Font-Underline="True|False"
    ForeColor="color name|#dddddd"
    Height="size"
    ID="string"
    OnDataBinding="DataBinding event handler"
    OnDataBound="DataBound event handler"
    OnDisposed="Disposed event handler"
    OnInit="Init event handler"
    OnLoad="Load event handler"
    OnPreRender="PreRender event handler"
    OnSelectedIndexChanged="SelectedIndexChanged event handler"
    OnTextChanged="TextChanged event handler"
    OnUnload="Unload event handler"
    Rows="integer"
    runat="server"
    SelectedIndex="integer"
    SelectedValue="string"
    SelectionMode="Single|Multiple"
    SkinID="string"
    Style="string"
    TabIndex="integer"
    ToolTip="string"
    ValidationGroup="string"
    Visible="True|False"
    Width="size"
>
            <asp:ListItem
                Enabled="True|False"
                Selected="True|False"
                Text="string"
                Value="string"
            />
</asp:ListBox>

Remarks

Use the ListBox control to create a list control that allows single or multiple item selection. Use the Rows property to specify the height of the control. To enable multiple item selection, set the SelectionMode property to Multiple.

To specify the items that you want to appear in the ListBox control, place a ListItem element for each entry between the opening and closing tags of the ListBox control.

The ListBox control also supports data binding. To bind the control to a data source, first create a data source, such as one of the DataSourceControl objects, that contains the items to display in the control. Next, use the DataBind method to bind the data source to the ListBox control. Use the DataTextField and DataValueField properties to specify which field in the data source to bind to the Text and Value properties, respectively, of each list item in the control. The ListBox control will now display the information from the data source.

If the SelectionMode property is set to Multiple, determine the selected items in the ListBox control by iterating through the Items collection and testing the Selected property of each item in the collection. If the SelectionMode property is set to Single, you can use the SelectedIndex property to determine the index of the selected item. The index can then be used to retrieve the item from the Items collection.

For detailed information on the ListBox Web server control's properties and events, see the ListBox class documentation.

Example

The following example demonstrates how to use the ListBox control to display a list of predefined options to the user. The item chosen by the user is displayed in a Label control.

<%@ Page Language="VB" AutoEventWireup="True" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>ListBox Example</title>
<script language="VB" runat="server">

    Sub SubmitBtn_Click(sender As Object, e As EventArgs)
        If ListBox1.SelectedIndex > - 1 Then
            Label1.Text = "You chose: " & ListBox1.SelectedItem.Text
        End If
    End Sub 'SubmitBtn_Click

  </script>

</head>
<body>

   <h3>ListBox Example</h3>

   <form id="form1" runat="server">

      <asp:ListBox id="ListBox1" 
           Rows="6"
           Width="100px"
           SelectionMode="Single" 
           runat="server">

         <asp:ListItem>Item 1</asp:ListItem>
         <asp:ListItem>Item 2</asp:ListItem>
         <asp:ListItem>Item 3</asp:ListItem>
         <asp:ListItem>Item 4</asp:ListItem>
         <asp:ListItem>Item 5</asp:ListItem>
         <asp:ListItem>Item 6</asp:ListItem>

      </asp:ListBox>

      <asp:button id="Button1"
           Text="Submit" 
           OnClick="SubmitBtn_Click" 
           runat="server" />
        
      <asp:Label id="Label1" 
           Font-Names="Verdana" 
           Font-Size="10pt" 
           runat="server"/>
        
   </form>

</body>
</html>
<%@ Page Language="C#" AutoEventWireup="True" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>ListBox Example</title>
<script language="C#" runat="server">

      void SubmitBtn_Click(Object sender, EventArgs e) 
      {
         if (ListBox1.SelectedIndex > -1)
            Label1.Text="You chose: " + ListBox1.SelectedItem.Text;
      }

   </script>

</head>
<body>

   <h3>ListBox Example</h3>

   <form id="form1" runat="server">

      <asp:ListBox id="ListBox1" 
           Rows="6"
           Width="100px"
           SelectionMode="Single" 
           runat="server">

         <asp:ListItem>Item 1</asp:ListItem>
         <asp:ListItem>Item 2</asp:ListItem>
         <asp:ListItem>Item 3</asp:ListItem>
         <asp:ListItem>Item 4</asp:ListItem>
         <asp:ListItem>Item 5</asp:ListItem>
         <asp:ListItem>Item 6</asp:ListItem>

      </asp:ListBox>

      <asp:button id="Button1"
           Text="Submit" 
           OnClick="SubmitBtn_Click" 
           runat="server" />
        
      <asp:Label id="Label1" 
           Font-Names="Verdana" 
           Font-Size="10pt" 
           runat="server"/>
        
   </form>

</body>
</html>

See Also

Reference

ListBox

Other Resources

Web Server Control Syntax