Using Global.asax to Check if User is Logged in each page lo

I suggest you to use web.config or base page to deny the access of page to unauthorized user.

Web.config:















Base page:

public class BasePage : System.Web.UI.Page
{

public user secure_username
{get;set;}

protected void Page_Load(object sender, EventArgs e)
{
//add your checks that repeat on each page
}
}

Other pages:

public class AuthenticatedUsersPage : BasePage
{

}

For more info: http://www.asp.net/web-forms/tutorials/security/membership/user-based-authorization-cs