Oct 23, 2015 02:28 AM|Klein Zhang|LINK
I would like to add the ID as a Claim to current User.
I'm not sure why you want to add Id as a Claim. In my experience, you could try with the code below to add claims.
var identity = (ClaimsIdentity)User.Identity;
IEnumerable<Claim> claims = identity.Claims;
claims .AddClaim(new Claim(ClaimTypes.Role, "guest"));
claims .AddClaim(new Claim(ClaimTypes.GivenName, "A Person"));
claims .AddClaim(new Claim(ClaimTypes.Sid, user.userID));
IsPersistent = model.RememberMe
Besides, About using Claims in asp.net Identity, you could refer to the following links.
I hope it's helpful to you.