<%@ Page Language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Protected Sub SubmitBtn_Click(ByVal sender As Object, ByVal e As System.EventArgs)
FirstSelect.Attributes.Add("Multiple", "True")
End Sub
</script>
<html >
<head runat="server">
<title>AttributeCollection Example</title>
</head>
<body>
<form id="form1" runat="server">
<div>
Make a selection:
<select id="FirstSelect"
runat="server">
<option>This</option>
<option>That</option>
<option>Other</option>
</select>
<br/><br/>
<input type="submit"
id="SubmitBtn"
value="Modify Attribute"
onserverclick="SubmitBtn_Click"
runat="server"/>
</div>
</form>
</body>
</html>