How to work iframe in Link label Click?

Steps

1     

                1)     Create a New Web application in Asp.net

            2)      Then type this java Script code  in Head tag

<asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent">

   <script type="text/javascript">

         function showIframe()

         {

            var iframe = document.getElementById("<%=iframe1.ClientID %>");

                   iframe.setAttribute("src", "Newpage.aspx");

                   iframe.style.display = "block";

            

         }

       </script>

     </asp:Content>

3              3)      Then Create a Iframe and call the fuction in LinkLabel onClientClick Event

   

<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">

           <iframe id="iframe1" runat="server style="display:none;" />

        <asp:LinkButton ID="lLife" runat="server" OnClientClick="showIframe(); return                       false;">Link</asp:LinkButton>

  

   </asp:Content>

       

       4)Then Run the Program and click in the Link