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Cross-Page Postback

You can have the buttons in your toolbar cause postbacks to a different Web page from the one that contains them. Simply set the PostBackUrl property to the page that should handle the postback. You can set the PostBackUrl for the entire toolbar, or for individual buttons. If you set the PostBackUrl in both places, the URL of the button overrides the setting on the toolbar:

<telerik:RadToolBar RenderMode="Lightweight" ID="RadToolBar1" runat="server" Skin="Outlook" PostBackUrl="CrossPage.aspx">
        <telerik:RadToolBarButton runat="server" Text="Button1" PostBackUrl="PageA.aspx" />
        <telerik:RadToolBarButton runat="server" Text="Button2">

Once in the second page, you can access the the toolbar (or any other control) on the previous page using the Page.PreviousPage property.

public partial class CrossPage : XhtmlPage
    protected void Page_Load(object sender, EventArgs e)   
        if (Page.PreviousPage == null)      

        RadToolBar toolBar = (RadToolBar)Page.PreviousPage.FindControl("RadToolBar1");   
Partial Class CrossPage  Inherits System.Web.UI.Page

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
        If Page.PreviousPage Is Nothing Then
        End If
        Dim toolbar As RadToolBar
        toolbar = CType(Page.PreviousPage.FindControl("RadToolBar1"), RadToolBar)
    End Sub

End Class   
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