<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="Default"
    MasterPageFile="~/MasterPage.master" %>

<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="ajax" %>
<asp:Content ID="Content1" runat="server" ContentPlaceHolderID="ContentPlaceHolder1">
    <telerik:RadAjaxManagerProxy ID="RadAjaxManagerProxy1" runat="server">
        <AjaxSettings>
            <telerik:AjaxSetting AjaxControlID="ComboBox1">
                <UpdatedControls>
                    <telerik:AjaxUpdatedControl ControlID="ComboBox1" />
                </UpdatedControls>
            </telerik:AjaxSetting>
            <telerik:AjaxSetting AjaxControlID="Button1">
                <UpdatedControls>
                    <telerik:AjaxUpdatedControl ControlID="Panel1" />
                </UpdatedControls>
            </telerik:AjaxSetting>
        </AjaxSettings>
    </telerik:RadAjaxManagerProxy>
    <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button" />
    <asp:Panel ID="Panel1" runat="server" Height="20px" Width="100px">
        <asp:Label ID="Label1" runat="server" Text="Label" Visible="False"></asp:Label>
    </asp:Panel>
    Content page combo:
    <ajax:ComboBox ID="ComboBox1" runat="server" AutoPostBack="true" OnSelectedIndexChanged="ComboBox1_SelectedIndexChanged">
        <asp:ListItem Text="Text1" />
        <asp:ListItem Text="Text2" />
        <asp:ListItem Text="Text3" />
        <asp:ListItem Text="Text4" />
        <asp:ListItem Text="Text5" />
    </ajax:ComboBox>
</asp:Content>
