public void IdentitySignin(UserCredential user, string providerKey = null, bool isPersistent = false)
{
var claims = new List <Claim>();
// create required claims
claims.Add(new Claim(ClaimTypes.NameIdentifier, user.UserID.ToString()));
claims.Add(new Claim(ClaimTypes.Name, user.Email));
// custom – my serialized AppUserState object
claims.Add(new Claim("userState", user.ToString()));
var identity = new ClaimsIdentity(claims, DefaultAuthenticationTypes.ApplicationCookie);
AuthenticationManager.SignIn(new AuthenticationProperties()
{
AllowRefresh = true,
IsPersistent = isPersistent,
ExpiresUtc = DateTime.UtcNow.AddDays(7)
}, identity);
}