How to add values to claims and retrieve it from web api - .Net core

Question

I am using Asp .net core 2.1

How to add custom claims after login?

Answer 1

in order to add custom claims after login, you can use the AddClaim method over a new ClaimsIdentity instance

var claims = new List<Claim>();
claims.Add(new Claim(ClaimTypes.Name, "some Name"));
claims.Add(new Claim(ClaimTypes.Email, "abc@xyz.com"));
var identity = new ClaimsIdentity(claims, DefaultAuthenticationTypes.ApplicationCookie);

var ctx = Request.GetOwinContext();
var authenticationManager = ctx.Authentication;
authenticationManager.SignIn(identity);

Then to retrieve the claims, you can use the LINQ over the ClaimsPrincipal instance:

var identity = (ClaimsPrincipal)Thread.CurrentPrincipal;
string email = identity.Claims.Where(c => c.Type == ClaimTypes.Email).Select(c => c.Value).SingleOrDefault();

Update: While trying to explore and fix the issue myself, I found this answer which works as an alternate solution to your problem.