how to get userid in aspnet core api project?

John Davis

previously I was using AspNet Microsoft.AspNet.Identity; to get the current user ID accessing api with following code

string userId = User.Identity.GetUserId();

Now I migrated whole project from AspNet to AspNetCore but how can I get current user ID accessing api?

Tried following code which returned username

var userName = User.FindFirstValue(ClaimTypes.Name);

I googled and found I have to use the following code to get userID,

var userId = User.FindFirstValue(ClaimTypes.NameIdentifier);

but it returned with 204, No Content

7 Replies

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John Davis4y ago
@Sachin Singh how can i change getting user by name to Email or PhoneNumber field?
like :-
_userManager.FindByNameAsync(User.Identity.Email); or _userManager.FindByNameAsync(User.Identity.PhoneNumber);
+2
John Davis4y ago
@Sachin Singh , I Finally found a solution with your suggested code
```
var user = await _userManager.FindByNameAsync(User.Identity.Name);
var userId = user?.Id;
```
+3
John Davis4y ago
@Sachin Singh Can you please explain? my project is an Rest api project cloned from

https://www.c-sharpcorner.com/article/jwt-authentication-with-refresh-tokens-in-net-6-0/
+2
Sachin Singh4y ago
so are you not using userManger ? its a basic class in core identity too as we had in old identity.
Make sure IUserManager is added to your DI container (using services.Add())
+2
John Davis4y ago
@Sachin Singh Thank you, but it returns me
1. System.NullReferenceException: Object reference not set to an instance of an object.
+2
Sachin Singh4y ago
You can test this
var user=await_userManager.GetUserAsync(HttpContext.User);
var userId = user?.Id;
+3
Amit Mohanty4y ago
Check the below link, this may help you.

https://www.koskila.net/how-to-get-current-user-in-asp-net-core/
+3