ASP.NET MVC - Set custom IIdentity or IPrincipal

Question

I need to do something fairly simple: in my ASP.NET MVC application, I want to set a custom IIdentity / IPrincipal. Whichever is easier / more suitable. I want to extend the

Answer 1

Here is an example to get the job done. bool isValid is set by looking at some data store (lets say your user data base). UserID is just an ID i am maintaining. You can add aditional information like email address to user data.

protected void btnLogin_Click(object sender, EventArgs e)
{         
    //Hard Coded for the moment
    bool isValid=true;
    if (isValid) 
    {
         string userData = String.Empty;
         userData = userData + "UserID=" + userID;
         FormsAuthenticationTicket ticket = new FormsAuthenticationTicket(1, username, DateTime.Now, DateTime.Now.AddMinutes(30), true, userData);
         string encTicket = FormsAuthentication.Encrypt(ticket);
         HttpCookie faCookie = new HttpCookie(FormsAuthentication.FormsCookieName, encTicket);
         Response.Cookies.Add(faCookie);
         //And send the user where they were heading
         string redirectUrl = FormsAuthentication.GetRedirectUrl(username, false);
         Response.Redirect(redirectUrl);
     }
}

in the golbal asax add the following code to retrive your information

protected void Application_AuthenticateRequest(Object sender, EventArgs e)
{
    HttpCookie authCookie = Request.Cookies[
             FormsAuthentication.FormsCookieName];
    if(authCookie != null)
    {
        //Extract the forms authentication cookie
        FormsAuthenticationTicket authTicket = 
               FormsAuthentication.Decrypt(authCookie.Value);
        // Create an Identity object
        //CustomIdentity implements System.Web.Security.IIdentity
        CustomIdentity id = GetUserIdentity(authTicket.Name);
        //CustomPrincipal implements System.Web.Security.IPrincipal
        CustomPrincipal newUser = new CustomPrincipal();
        Context.User = newUser;
    }
}

When you are going to use the information later, you can access your custom principal as follows.

(CustomPrincipal)this.User
or 
(CustomPrincipal)this.Context.User

this will allow you to access custom user information.