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ListBox Class

Represents a list box control that allows single or multiple item selection.

For a list of all members of this type, see ListBox Members.

System.Object
   System.Web.UI.Control
      System.Web.UI.WebControls.WebControl
         System.Web.UI.WebControls.ListControl
            System.Web.UI.WebControls.ListBox

[Visual Basic]
Public Class ListBox
   Inherits ListControl
   Implements IPostBackDataHandler
[C#]
public class ListBox : ListControl, IPostBackDataHandler
[C++]
public __gc class ListBox : public ListControl,
   IPostBackDataHandler
[JScript]
public class ListBox extends ListControl implements
   IPostBackDataHandler

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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 ListSelectionMode.Multiple.

Example

[Visual Basic, C#] The following example demonstrates how to create a ListBox control.

[Visual Basic] 
<%@ Page Language="VB" AutoEventWireup="True" %>

<html>
<head>

   <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 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-Name="Verdana" 
           Font-Size="10pt" 
           runat="server"/>
        
   </form>

</body>
</html>

[C#] 
<%@ Page Language="C#" AutoEventWireup="True" %>

<html>
<head>

   <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 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-Name="Verdana" 
           Font-Size="10pt" 
           runat="server"/>
        
   </form>

</body>
</html>

[Visual Basic, C#] The following example demonstrates how to create a ListBox control through data binding.

[Visual Basic] 
<%@ Page Language="VB" AutoEventWireup="True" %>

<html>
<head>

   <script language="VB" runat="server">

    Sub Page_Load(sender As Object, e As EventArgs)
        
        If Not IsPostBack Then
            
            Dim values As New ArrayList()
            
            values.Add("Item 1")
            values.Add("Item 2")
            values.Add("Item 3")
            values.Add("Item 4")
            values.Add("Item 5")
            values.Add("Item 6")
            
            ListBox1.DataSource = values
            ListBox1.DataBind()
        End If 
    End Sub 'Page_Load

    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>

   <form runat=server>

        <h3>Data Binding ListBox</h3>
    
        <asp:ListBox id="ListBox1" 
             Width="100px" 
             runat="server"/>

        <asp:button id="Button1"
             Text="Submit" 
             OnClick="SubmitBtn_Click" 
             runat="server" />
        
        <asp:Label id="Label1" 
             font-name="Verdana" 
             font-size="10pt" 
             runat="server"/>

   </form>

</body>
</html>

[C#] 
<%@ Page Language="C#" AutoEventWireup="True" %>

<html>
<head>

   <script language="C#" runat="server">

      void Page_Load(Object sender, EventArgs e) 
      {

         if (!IsPostBack) 
         {

            ArrayList values = new ArrayList();

            values.Add ("Item 1");
            values.Add ("Item 2");
            values.Add ("Item 3");
            values.Add ("Item 4");
            values.Add ("Item 5");
            values.Add ("Item 6");

            ListBox1.DataSource = values;
            ListBox1.DataBind();

         }

      }

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

   </script>

</head>
<body>

   <form runat=server>

        <h3>Data Binding ListBox</h3>
    
        <asp:ListBox id="ListBox1" 
             Width="100px" 
             runat="server"/>

        <asp:button id="Button1"
             Text="Submit" 
             OnClick="SubmitBtn_Click" 
             runat="server" />
        
        <asp:Label id="Label1" 
             font-name="Verdana" 
             font-size="10pt" 
             runat="server"/>

   </form>

</body>
</html>

[C++, JScript] No example is available for C++ or JScript. To view a Visual Basic or C# example, click the Language Filter button Language Filter in the upper-left corner of the page.

Requirements

Namespace: System.Web.UI.WebControls

Platforms: Windows 2000, Windows XP Professional, Windows Server 2003 family

Assembly: System.Web (in System.Web.dll)

See Also

ListBox Members | System.Web.UI.WebControls Namespace | ListControl | ListItem | ListItemCollection

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