Radgrid下拉列表onchange

I am trying to refresh asp.net label contorls outside the grid when I change the RadGrid dropdownlist. I don't what to postback entire page. Is there anyway I can refresh using Ajax techinique? Please let me know.

Thank you for any help.

Wrap the grid, and any controls outside of the grid that need to be updated asynchronously inside of a RadAjaxPanel.

<telerik:RadAjaxPanel ID="RadAjaxPanel1" runat="server">
    <asp:Label ID="Label1" runat="server" />
    <telerik:RadGrid ID="RadGrid1" runat="server">
        ...
    </telerik:RadGrid>
</telerik:RadAjaxPanel>

EDIT: Seeing your last comment, it would be more appropriate to use a RadAjaxManager, like this:

<telerik:RadAjaxManager ID="RadAjaxManager1" runat="server" ...>
    <AjaxSettings>
        <telerik:AjaxSetting AjaxControlID="RadGrid1">
            <UpdatedControls>
                <telerik:AjaxUpdatedControl ControlID="Label1" />
                <telerik:AjaxUpdatedControl ControlID="Label2" />
            </UpdatedControls>
        </telerik:AjaxSetting>
    </AjaxSettings>
</telerik:RadAjaxManager> 

The Telerik article you posted in your comments (the tutorial you are following) is very old and as such uses an old version of the Telerik controls.

I have built an example which hopefully will provide you with a starting point for what you are trying to achieve, however it uses the Telerik ASP.NET Ajax 2010 controls (I assume they have not changed that much in the 2011 version you can download).

Here it is:

Markup

<%@ Register TagPrefix="telerik" Namespace="Telerik.Web.UI" Assembly="Telerik.Web.UI" %>

....

<asp:ScriptManager ID="scriptManager" runat="server"></asp:ScriptManager>
<telerik:RadAjaxPanel ID="radAjax" runat="server">
    <telerik:RadGrid ID="radGrid" runat="server" GridLines="None" Width="100%">
        <MasterTableView AutoGenerateColumns="False">
        <Columns>
            <telerik:GridTemplateColumn>
                <ItemTemplate>
                    <telerik:RadComboBox ID="comboBox1" runat="server" OnSelectedIndexChanged="cbm_SelectedIndexChanged" AutoPostBack="true">
                        <Items>
                            <telerik:RadComboBoxItem Text="Item 1" Value="Value 1" />
                            <telerik:RadComboBoxItem Text="Item 2" Value="Value 2" />
                            <telerik:RadComboBoxItem Text="Item 3" Value="Value 3" />
                        </Items>
                    </telerik:RadComboBox>
                </ItemTemplate>
            </telerik:GridTemplateColumn>
        </Columns>
        </MasterTableView>                    
    </telerik:RadGrid>   
    <asp:Label ID="label1" runat="server"></asp:Label>              
</telerik:RadAjaxPanel> 

Code

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        //Quick data bind for the example
        var data = new[] { new { Value = "1" }, new { Value = "2" } };
        radGrid.DataSource = data;
        radGrid.DataBind();
    }
}

protected void cbm_SelectedIndexChanged(object o, Telerik.Web.UI.RadComboBoxSelectedIndexChangedEventArgs e)
{
    //Retrieve a reference to the combobox if needed
    RadComboBox comboBox = (RadComboBox)o;

    //Set the label text to the value of the combobox item selected
    label1.Text = e.Value + comboBox.ID;
}

Hope this helps.