HtmlSelect.Multiple Property
Gets or sets a value indicating whether multiple items can be selected concurrently in the HtmlSelect control.
Assembly: System.Web (in System.Web.dll)
Property Value
Type: System.Booleantrue if multiple items can be concurrently selected in the HtmlSelect control; otherwise, false. The default value is false.
Use the Multiple property to specify whether multiple items can be concurrently selected in the HtmlSelect control.
By default, the HtmlSelect control is displayed as a drop-down list box. If you allow multiple selections (by setting the Multiple property to true) or specify a height greater than one row (by setting the Size property to a value greater than 1), the control is displayed as a list box.
To determine the selected items in an HtmlSelect control that allows multiple simultaneous selections, iterate through the Items collection and test the ListItem.Selected property of each item.
Note |
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The multiple attribute is rendered in the HtmlSelect control only if this property is set to true. |
The following code example demonstrates how to use the Multiple property to specify whether multiple items can be selected in the HtmlSelect control.
<%@ Page Language="C#" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <script runat="server"> void Button_Click (Object sender, EventArgs e) { Label1.Text = "You selected:"; for (int i=0; i<=Select1.Items.Count - 1; i++) { if (Select1.Items[i].Selected) Label1.Text += "<br /> -" + Select1.Items[i].Text; } Select1.Size = Convert.ToInt32(Select2.Value); } void Check_Changed (Object sender, EventArgs e) { Select1.Multiple = CheckBox1.Checked; } </script> <html xmlns="http://www.w3.org/1999/xhtml" > <head> <title> HtmlSelect Example </title> </head> <body> <form id="form1" runat="server"> <div> <h3> HtmlSelect Example </h3> Select item(s) from the list: <br /><br /> <select id="Select1" multiple="true" runat="server"> <option value="1" selected="selected"> Item 1 </option> <option value="2"> Item 2 </option> <option value="3"> Item 3 </option> <option value="4"> Item 4 </option> <option value="5"> Item 5 </option> <option value="6"> Item 6 </option> </select> <hr /> HtmlSelect Size: <br /> <select id="Select2" runat="server"> <option value="1"> 1 </option> <option value="2"> 2 </option> <option value="3"> 3 </option> <option value="4" selected="selected"> 4 </option> <option value="5"> 5 </option> <option value="6"> 6 </option> </select> <asp:CheckBox id="CheckBox1" Text="Enable Multiple Property" AutoPostBack="True" OnCheckedChanged="Check_Changed" Checked="True" runat="server"/> <br /><br /> <button id="Button1" onserverclick="Button_Click" runat="server"> Submit </button> <br /><br /> <asp:Label id="Label1" runat="server"/> </div> </form> </body> </html>
Available since 1.1
