< %@ Page Language="VB" AutoEventWireup="false" CodeFile="Default.aspx.vb" Inherits="_Default" %> 

< !DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
< html xmlns="http://www.w3.org/1999/xhtml"> 
< head runat="server"> 
    < title> Untitled Page< /title> 

    < script type="text/javascript"> 

function table_count()
{
alert(document.getElementsByTagName("table").length);
}

    < /script> 

< /head> 
< body> 
    < form id="form1" runat="server"> 
    < div> 
        < table> 
            < tr> 
                < td> 
                   First table
                < /td> 
            < /tr> 
        < /table> 
        < table> 
            < tr> 
                < td> 
                    Second Table
                < /td> 
                < td> 
                < asp:Button ID="Button1" runat="server" Text="Button" OnClientClick="table_count()" /> 
                < /td> 
            < /tr> 
        < /table> 
    < /div> 
    < /form> 
< /body> 
< /html>