<%@ Page Language="VB" %>
<script runat="server">
Protected Sub DropDownList1_SelectedIndexChanged(ByVal sender As Object, _
ByVal e As System.EventArgs)
Dim CarArray() As String = {"Ford", "Honda", "BMW", "Dodge"}
Dim AirplaneArray() As String = {"Boeing 777", "Boeing 747", "Boeing 737"}
Dim TrainArray() As String = {"Bullet Train", "Amtrack", "Tram"}
If DropDownList1.SelectedValue = "Car" Then
DropDownList2.DataSource = CarArray
ElseIf DropDownList1.SelectedValue = "Airplane" Then
DropDownList2.DataSource = AirplaneArray
Else
DropDownList2.DataSource = TrainArray
End If
DropDownList2.DataBind()
DropDownList2.Visible = True
End Sub
Protected Sub Button1_Click(ByVal sender As Object, _
ByVal e As System.EventArgs)
Response.Write("You selected <b>" & _
DropDownList1.SelectedValue.ToString() & ": " & _
DropDownList2.SelectedValue.ToString() & "</b>")
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>DropDownList Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
Select transportation type:<br />
<asp:DropDownList ID="DropDownList1" Runat="server"
OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged"
AutoPostBack="true">
<asp:ListItem>Select an Item</asp:ListItem>
<asp:ListItem>Car</asp:ListItem>
<asp:ListItem>Airplane</asp:ListItem>
<asp:ListItem>Train</asp:ListItem>
</asp:DropDownList>
<asp:DropDownList ID="DropDownList2" Runat="server" Visible="false">
</asp:DropDownList>
<asp:Button ID="Button1" Runat="server" Text="Select Options"
OnClick="Button1_Click" />
</div>
</form>
</body>
</html>