
<script  runat="server">
Sub submit(Sender As Object, e As EventArgs)
   label1.Text=txt1.Text
End Sub
</script>

<html>
<body>

<form runat="server">
：
<asp:TextBox id="txt1" Width="200" runat="server" />
<asp:Button id="b1" Text="复制到 Label" OnClick="submit" runat="server" />
<p><asp:Label id="label1" runat="server" /></p>
</form>

</body>
</html>