PrivateSub Page_Load()Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) HandlesMyBase.Load
'在此处放置初始化页的用户代码 IfNot Page.IsPostBack Then Dim a AsNew ListItem("asp", "images/Title-MC2222.gif")
'用listitem 对象的实例时可以指定标签与选定值属性 Dim b AsNew ListItem("php", "images/Title-MC3026.gif")
DropDownList1.Items.Add(a)
DropDownList1.Items.Add(b)
Image1.Visible =False EndIf End Sub PrivateSub DropDownList1_SelectedIndexChanged()Sub DropDownList1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles DropDownList1.SelectedIndexChanged
Image1.Visible =True Image1.ImageUrl = DropDownList1.SelectedItem.Value
End Sub