Here Andrew Zhu, has explained how to generate  net formsauthentication asp.net.

Assume you are using FormsAuthentication.RedirectFromLoginPage() to direct user's request after loging in.

Now, you want the request to be redirected to different pages up to different users. you may need to write you own code to achieve this:

Validate user using Membersip

if (Membership.ValidateUser(TextBox1.Text, TextBox2.Text))      {    // Generate FormsAuthentication ticket             FormsAuthenticationTicket tkt = new FormsAuthenticationTicket(TextBox1.Text, true, 10);    // FormsAuthntication encrypt ticket             string cookiestring = FormsAuthentication.Encrypt(tkt);    //Create cookie FormsAuthentication Cookie             HttpCookie httpCookie = new HttpCookie(FormsAuthentication.FormsCookieName, cookiestring);    // Give cookie FormsAuthnetication Cookie path             httpCookie.Path = FormsAuthentication.FormsCookiePath;    // Send cookie in response             Response.Cookies.Add(httpCookie);             //then, redirect whatever page you want here             Response.Redirect("url"); }