ListSelectionMode Enumeration

Specifies the selection mode of the ListBox control.

Namespace: System.Web.UI.WebControls
Assembly: System.Web (in system.web.dll)

Public Enumeration ListSelectionMode
Dim instance As ListSelectionMode

public enum ListSelectionMode
public enum ListSelectionMode

 Member nameDescription
MultipleMultiple item selection mode. 
SingleSingle item selection mode. 

The ListSelectionMode enumeration represents the selection mode of the ListBox control that determines whether a user can select multiple items or just a single item.

<!-- This example demonstrates how to select multiple items from a DataList 
and add the selected items to a DataGrid. The example uses a For Each loop 
to iterate through the ListItem objects in the ListItemCollection of ListBox1. -->

...<%@ Page language="VB" AutoEventWireup="true"%>
<%@ Import Namespace="System.Data" %>

        <SCRIPT runat="server">
            ' Global Variables.
            Private dv As DataView
            Private dt As New DataTable()

            Private Sub Page_Load(sender As Object, e As System.EventArgs)
                ' Set the number of rows displayed in the ListBox to be
                ' the number of items in the ListBoxCollection.
                ListBox1.Rows = ListBox1.Items.Count

                ' If the DataTable is already stored in the Web form's default
                ' HttpSessionState variable, then don't recreate the DataTable.
                If Session("data") Is Nothing Then
                    ' Add columns to the DataTable.
                    dt.Columns.Add(New DataColumn("Item"))
                    dt.Columns.Add(New DataColumn("Price"))
                    ' Store the DataTable in the Session variable so it can be 
                    ' accessed again later.
                    Session("data") = dt
                    ' Use the table to create a DataView, because the DataGrid
                    ' can only bind to a data source that implements IEnumerable.
                    dv = New DataView(dt)
                    ' Set the DataView as the data source, and bind it to the DataGrid.
                    DataGrid1.DataSource = dv
                End If
            End Sub

            Private Sub addButton_Click(sender As Object, e As System.EventArgs)
                ' Add the items selected in ListBox1 to DataGrid1.
                Dim item As ListItem
                For Each item In ListBox1.Items
                    If item.Selected Then
                        ' Add the item to the DataGrid.
                        ' First, get the DataTable from the Session variable.
                        dt = CType(Session("data"), DataTable)
                        If  Not (dt Is Nothing) Then
                            ' Create a new DataRow in the DataTable.
                            Dim dr As DataRow
                            dr = dt.NewRow()
                            ' Add the item to the new DataRow.
                            dr("Item") = item.Text
                            ' Add the item's value to the DataRow.
                            dr("Price") = item.Value
                            ' Add the DataRow to the DataTable.

                            ' Rebind the data to DataGrid1.
                            dv = new DataView(dt)
                            DataGrid1.DataSource = dv
                        End If
                    End If
                Next item
            End Sub

        <form runat="server">

            <h3> ListItemCollection Example </h3>

            <table cellpadding="6" border="0">
                    <td valign="top">
                        <asp:ListBox id="ListBox1" runat="server" SelectionMode="Multiple">
                            <asp:ListItem Value=".89">apples</asp:ListItem>
                            <asp:ListItem Value=".49">bananas</asp:ListItem>
                            <asp:ListItem Value="2.99">cherries</asp:ListItem>
                            <asp:ListItem Value="1.49">grapes</asp:ListItem>
                            <asp:ListItem Value="2.00">mangos</asp:ListItem>
                            <asp:ListItem Value="1.09">oranges</asp:ListItem>

                    <td valign="top">
                        <asp:Button id="addButton" runat="server" Text="Add -->"
                            Width="100px" OnClick="addButton_Click"></asp:Button>

                    <td valign="top">
                        <asp:DataGrid Runat="server" ID="DataGrid1" CellPadding="4">

Windows 98, Windows 2000 SP4, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.

.NET Framework

Supported in: 2.0, 1.1, 1.0

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