Sub choose_image(Sender As Object, e As EventArgs)
image1.Src = select1.Value
<select id="select1" runat="server">
<option value="/img/eg_smile.gif">笑脸</option>
<option value="/img/eg_bulbon.gif">灯泡</option>
<option value="/img/eg_mouse.jpg">鼠标</option>
<input type="submit" runat="server" value="显示图像"
OnServerClick="choose_image">
<img id="image1" src="/img/eg_smile.gif" runat="server" />