Check out example codes for "how to set the current user httpcontext.current.user asp.net -mvc". It will help you in understanding the concepts better.

Code Example 1

String[] newRoles = { "Administrator", "Customer" };
GenericIdentity newIdentity = new GenericIdentity(model.AccountName);
GenericPrincipal newPrincipal = new GenericPrincipal(newIdentity, newRoles);                       
System.Web.HttpContext.Current.User = newPrincipal;

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