Given the following code below. How might I display another web page or content within the placeholder via a server onClick event in C# code; similar to now defunct iframe. I perfer to handle all events via sever side code (C#, asp.net 4.0)
<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server"></asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContentPlaceHolder"
runat="Server">
<asp:PlaceHolder runat="server" ID="PlaceHolder1">
</asp:PlaceHolder>
</asp:Content>
<asp:Content ID="Content3" ContentPlaceHolderID="NavigationContentPlaceHolder" Runat="Server">
<uc1:NavigationUserControl runat="server" ID="NavigationUserControl" />
</asp:Content>
Thank you in advance!