Here's one solution but it's not the best.
I'm not a js expert and my colleage told me that with jquery this issue can be solved perfectly.
OK. Please refer to my solution.
In headermenu.ascx
Replace <a> tag with
<asp:HyperLink runat="server" id="Menu_Example" NavigateUrl="~/default.aspx">Home</asp:HyperLink >
In headermenu.ascx.cs
Put following code in Page_Load() method
if (Request.Url.AbsolutePath == "/default.aspx" || Request.Url.AbsolutePath == "/Default.aspx")
{
Menu_Product.CssClass = "menu_clicked";
}
You also need to create a new class”menu_clicked” in styles.css file.
Regards.
Larry