ajax: PopupControlExtender使用

示例效果：
通过(asp:RadioButtonList) radlst_RegKind的点选
将所行值提交给(asp:TextBox) txt_RegKind
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HTML部分的代码示例如下：

<%@ Register Assembly="AjaxControlToolkit"
    Namespace="AjaxControlToolkit" TagPrefix="cc1" %>

<form id="form1" runat="server">
        <asp:ScriptManager ID="ScriptManager1" runat="server">
        </asp:ScriptManager>
  <asp:UpdatePanel ID="UpdatePanel1" runat="server">
    <ContentTemplate>
        <asp:TextBox ID="txt_RegKind" runat="server" ></asp:TextBox>
        <cc1:PopupControlExtender ID="popCtl_RegKind" runat="server"
        TargetControlID="txt_RegKind" PopupControlID="pnl_RegKind"
        CommitProperty="" CommitScript="" Position="Bottom" >
        </cc1:PopupControlExtender>
        <asp:Panel ID="pnl_RegKind" runat="server" CssClass="popupControl">
            <asp:RadioButtonList ID="radlst_RegKind" runat="server" AutoPostBack="True"
            OnSelectedIndexChanged="radlst_RegKind_SelectedIndexChanged" Width="130px">
                <asp:ListItem Value="1">1.非农业户口</asp:ListItem>
                <asp:ListItem Value="2">2.农业户口</asp:ListItem>
                <asp:ListItem Value="9">9.其他</asp:ListItem>
            </asp:RadioButtonList>
        </asp:Panel>
    </ContentTemplate>
</asp:UpdatePanel>

</form>

后台cs部分的代码示例如下
    protected void radlst_RegKind_SelectedIndexChanged(object sender, EventArgs e)
    {
        popCtl_RegKind.Commit(this.radlst_RegKind.SelectedItem.Text);
    }