.NET Framework Class Library
ListSelectionMode Enumeration
Specifies the selection mode of the ListBox control.
Assembly: System.Web (in System.Web.dll)
Syntax
Visual Basic
Public Enumeration ListSelectionMode
C#
public enum ListSelectionMode
Visual C++
public enum class ListSelectionMode
F#
type ListSelectionMode
Members
| Member name | Description | |
|---|---|---|
| Single | Single item selection mode. | |
| Multiple | Multiple item selection mode. |
Remarks
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.
Examples
Visual Basic
<!-- 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" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <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 DataGrid1.DataBind() 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. dt.Rows.Add(dr) ' Rebind the data to DataGrid1. dv = new DataView(dt) DataGrid1.DataSource = dv DataGrid1.DataBind() End If End If Next item End Sub </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head> <title> ListItemCollection Example </title> </head> <body> <form id="form1" runat="server"> <h3> ListItemCollection Example </h3> <table cellpadding="6" border="0"> <tr> <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> </asp:ListBox> </td> <td valign="top"> <asp:Button id="addButton" runat="server" Text="Add -->" Width="100px" OnClick="addButton_Click"></asp:Button> </td> <td valign="top"> <asp:DataGrid Runat="server" ID="DataGrid1" CellPadding="4"> </asp:DataGrid> </td> </tr> </table> </form> </body> </html>
C#
<!-- This example demonstrates how to select multiple items from a DataList and add the selected items to a DataGrid. The example uses a foreach loop to iterate through the ListItem objects in the ListItemCollection of ListBox1. --> ... <%@ Page language="c#" AutoEventWireup="true"%> <%@ Import Namespace="System.Data" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script language="C#" runat="server"> // Global Variables. private DataView dv; private DataTable dt = new DataTable(); private void Page_Load(object sender, System.EventArgs e) { // 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"] == null) { // 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; DataGrid1.DataBind(); } } private void addButton_Click(object sender, System.EventArgs e) { // Add the items selected in ListBox1 to DataGrid1. foreach (ListItem item in ListBox1.Items) { if (item.Selected) { // Add the item to the DataGrid. // First, get the DataTable from the Session variable. dt = (DataTable)Session["data"]; if (dt != null) { // Create a new DataRow in the DataTable. 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. dt.Rows.Add(dr); // Rebind the data to DataGrid1. dv = new DataView(dt); DataGrid1.DataSource = dv; DataGrid1.DataBind(); } } } } </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head> <title> ListItemCollection Example </title> </head> <body> <form id="form1" runat="server"> <h3> ListItemCollection Example </h3> <table cellpadding="6" border="0"> <tr> <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> </asp:ListBox> </td> <td valign="top"> <asp:Button id="addButton" runat="server" Text="Add -->" Width="100px" OnClick="addButton_Click"></asp:Button> </td> <td valign="top"> <asp:DataGrid Runat="server" ID="DataGrid1" CellPadding="4"> </asp:DataGrid> </td> </tr> </table> </form> </body> </html>
Version Information
.NET Framework
Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0Platforms
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
See Also