Informing ASP.NET website about the currently logged-in user - asp.net

Question

I'm new to ASP.NET and have been trying to solve this for awhile now.
I've came across this blog, and everything looks to be good, except one thing: the below code always evaluates to false in HttpContext.Current.User.Identity is FormsIdentity in this code snippit:
protected void Application_AuthenticateRequest(Object sender,
EventArgs e)
{
if (HttpContext.Current.User != null)
{
if (HttpContext.Current.User.Identity.IsAuthenticated)
{
if (HttpContext.Current.User.Identity is FormsIdentity)
{
FormsIdentity id =
(FormsIdentity)HttpContext.Current.User.Identity;
FormsAuthenticationTicket ticket = id.Ticket;
// Get the stored user-data, in this case, our roles
string userData = ticket.UserData;
string[] roles = userData.Split(',');
HttpContext.Current.User = new GenericPrincipal(id, roles);
}
}
}
}
When I used breakpoints, it turned that my PC name is the current user, which I think is not a FormsIdentity.
Web.config:
<?xml version="1.0"?>
<!--
For more information on how to configure your ASP.NET application, please visit
http://go.microsoft.com/fwlink/?LinkId=169433
-->
<configuration>
<system.web>
<compilation debug="true" targetFramework="4.0"/>
</system.web>
</configuration>
What am I missing here? and how to tell HttpContext of the current user after a sucessful login?

Answer 1

If you want users to have a FormsIdentity, then you need to turn on FormsAuthentication in your web.config file. In your element, you need to populate the authentication and authorization nodes. (For example, see the section of the blog post you mentioned titled "Securing Directories with Role-based Forms Authentication") Right now these elements are not present in your web.config file, and so Forms Authentication is not happening. A configuration like this is typical:
<system.web>
<authentication mode="Forms">
<forms name=".ASPXFORMSDEMO" loginUrl="logon.aspx" protection="All" path="/" timeout="30" />
</authentication>
<authorization>
<deny users ="?" />
<allow users = "*" />
</authorization>
</system.web>
The node instructs ASP.Net to use forms authentication, while the node denies access to the site for any user who is not authentication.
More information can be found here and here