Muokkaa

Jaa

ListBox.SelectionMode Property

  • Reference

Definition

Namespace:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Gets or sets the selection mode of the ListBox control.

public:
 virtual property System::Web::UI::WebControls::ListSelectionMode SelectionMode { System::Web::UI::WebControls::ListSelectionMode get(); void set(System::Web::UI::WebControls::ListSelectionMode value); };
public virtual System.Web.UI.WebControls.ListSelectionMode SelectionMode { get; set; }
member this.SelectionMode : System.Web.UI.WebControls.ListSelectionMode with get, set
Public Overridable Property SelectionMode As ListSelectionMode

Property Value

ListSelectionMode

One of the ListSelectionMode values. The default value is Single.

Exceptions

ArgumentOutOfRangeException

The specified selection mode is not one of the ListSelectionMode values.

Examples

The following example illustrates how to use the SelectionMode property to allow the user to select multiple selections from the ListBox control.


<%@ 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 runat="server">
    <title>ListBox Example</title>
<script runat="server">

      void SubmitBtn_Click(Object sender, EventArgs e) 
      {

         Message.Text = "You chose: <br />";
         
         // Iterate through the Items collection of the ListBox and 
         // display the selected items.
         foreach (ListItem item in ListBox1.Items)
         {

            if(item.Selected)
            {

               Message.Text += item.Text + "<br />";

            }

         }

      }

   </script>

</head>
<body>

   <h3>ListBox Example</h3>

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

      Select items from the list and click Submit. <br />

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

         <asp:ListItem Selected="True">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>

      <br /><br />

      <asp:button id="Button1"
           Text="Submit" 
           OnClick="SubmitBtn_Click" 
           runat="server" />

      <br /><br />
        
      <asp:Label id="Message" 
           runat="server"/>
        
   </form>

</body>
</html>


<%@ 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 runat="server">
    <title>ListBox Example</title>
<script runat="server">

      Sub SubmitBtn_Click(sender As Object, e As EventArgs) 

         Message.Text = "You chose: <br />"
         
         ' Iterate through the Items collection of the ListBox and 
         ' display the selected items.
         Dim item As ListItem
         For Each item in ListBox1.Items

            If item.Selected Then

               Message.Text &= item.Text & "<br />"

            End If

         Next

      End Sub

   </script>

</head>
<body>

   <h3>ListBox Example</h3>

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

      Select items from the list and click Submit. <br />

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

         <asp:ListItem Selected="True">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>

      <br /><br />

      <asp:button id="Button1"
           Text="Submit" 
           OnClick="SubmitBtn_Click" 
           runat="server" />

      <br /><br />
        
      <asp:Label id="Message" 
           runat="server"/>
        
   </form>

</body>
</html>

Remarks

Use the SelectionMode property to specify the mode behavior of the ListBox control. Setting this property to ListSelectionMode.Single indicates only a single item can be selected from the ListBox control, while ListSelectionMode.Multiple specifies multiple items can be selected.

The value of the SelectionMode property is stored in view state.

Applies to

See also