How to Get Current User in ASP.NET Core

How to get current user in asp.net core

User.FindFirst(ClaimTypes.NameIdentifier).Value

EDIT for constructor

Below code works:

public Controller(IHttpContextAccessor httpContextAccessor)
{
    var userId = httpContextAccessor.HttpContext.User.FindFirst(ClaimTypes.NameIdentifier).Value 
}

Edit for RTM

You should register IHttpContextAccessor:

    public void ConfigureServices(IServiceCollection services)
    {
        services.AddHttpContextAccessor();
    }

Getting Current User in Controller

You can get the current user id in your controller using the UserManager such as:

ASP.NET CORE >= 2.0

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

or Name using:

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

If you want to get the current user in some other class, you can use the IHttpContextAccessor, passing it into the class's constructor and using the HttpContext to access the User

Get current user id in startup (asp.net core 5)

I need to send user Id when inject some service. or it is not possible ?

HttpContext is only valid during a request. The ConfigureServices method in Startup is not a web call and, as such, does not have a HttpContext. So the User information also cannot be got. You need register the IHttpContextAccessor and DI it by constructor in your services. Then you could get HttpContext.User infomation successfully.

Register the IHttpContextAccessor:

services.AddScoped<IHttpContextAccessor,HttpContextAccessor>();

DI in the service:

public interface IService
{
    string GetUserId();
}

public class Service : IService
{
    private readonly IHttpContextAccessor _httpContextAccessor;
    public Service(IHttpContextAccessor httpContextAccessor)
    {
        _httpContextAccessor = httpContextAccessor;
    }
    public string GetUserId()
    {
        var id = _httpContextAccessor.HttpContext.User.FindFirst(ClaimTypes.NameIdentifier).Value;
        return id;
    }
}

Register the service:

services.AddScoped<IHttpContextAccessor,HttpContextAccessor>();
services.AddScoped<IService, Service>(); //add this...

More explanations you could refer to here.

ASP.NET Core Identity - get current user

If your code is inside an MVC controller:

public class MyController : Microsoft.AspNetCore.Mvc.Controller

From the Controller base class, you can get the ClaimsPrincipal from the User property

System.Security.Claims.ClaimsPrincipal currentUser = this.User;

You can check the claims directly (without a round trip to the database):

bool isAdmin = currentUser.IsInRole("Admin");
var id = _userManager.GetUserId(User); // Get user id:

Other fields can be fetched from the database's User entity:

1. Get the user manager using dependency injection

   private UserManager<ApplicationUser> _userManager;
   
   //class constructor
   public MyController(UserManager<ApplicationUser> userManager)
   {
       _userManager = userManager;
   }
   

2. And use it:

   var user = await _userManager.GetUserAsync(User);
   var email = user.Email;
   

If your code is a service class, you can use dependency injection to get an IHttpContextAccessor that lets you get the User from the HttpContext.

    private IHttpContextAccessor _httpContextAccessor;

    public MyClass(IHttpContextAccessor httpContextAccessor)
    {
        _httpContextAccessor = httpContextAccessor;
    }

    private void DoSomething()
    {
        var user = _httpContextAccessor.Context?.User;
    }

How to get current user id, if i inherits from IdentityUser?

In ASP.Net Core ,if your Controller inherits the Microsoft.AspNetCore.Mvc.Controller, you could get the IClaimsPrincipal from the User property and get the actual "Id" of the user,

using System.Security.Claims;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Identity;

ClaimsPrincipal currentUser = this.User;
var currentUserID = currentUser.FindFirst(ClaimTypes.NameIdentifier).Value;

You can also get the data of all fields(include Id) from the database's User entity:

1.DI UserManager

    private readonly UserManager<ApplicationUser> _userManager;

    public HomeController(UserManager<ApplicationUser> userManager)
    {
        _userManager = userManager;
    }

2.Use it like below:

var id = userManager.GetUserId(User); // get user Id
var user = await userManager.GetUserAsync(User); // get user's all data

How to get the current logged in user ID in ASP.NET Core?

I included using System.Security.Claims and I could access the GetUserId() extension method

NB: I had the using Microsoft.AspNet.Identity already but couldn't get the extension method. So I guess both of them have to be used in conjunction with one another

using Microsoft.AspNet.Identity;
using System.Security.Claims;

EDIT:
This answer is now outdated. Look at Soren's or Adrien's answer for a dated way of achieving this in CORE 1.0

What is the way in ASP.NET Core 3.0 to get current authenticated User username?

For this issue, it is caused by that the IdentityServer4 did not add the JwtClaimTypes.Name to the access_token. If you check the access_token from web brower, you will find it miss "name": "Tom", node.

For a workaround, you could implement your own ITokenService like

public class CustomTokenService : DefaultTokenService
{
    public CustomTokenService(IClaimsService claimsProvider
        , IReferenceTokenStore referenceTokenStore
        , ITokenCreationService creationService
        , IHttpContextAccessor contextAccessor
        , ISystemClock clock
        , IKeyMaterialService keyMaterialService
        , ILogger<DefaultTokenService> logger) 
        : base(claimsProvider, referenceTokenStore, creationService, contextAccessor, clock, keyMaterialService, logger)
    {
    }

    public override async Task<Token> CreateAccessTokenAsync(TokenCreationRequest request)
    {

        Logger.LogTrace("Creating access token");
        request.Validate();

        var claims = new List<Claim>();
        claims.AddRange(await ClaimsProvider.GetAccessTokenClaimsAsync(
            request.Subject,
            request.Resources,
            request.ValidatedRequest));

        if (request.ValidatedRequest.Client.IncludeJwtId)
        {
            claims.Add(new Claim(JwtClaimTypes.JwtId, CryptoRandom.CreateUniqueId(16)));
        }
        claims.Add(new Claim(JwtClaimTypes.Name, request.Subject.GetDisplayName()));
        var issuer = Context.HttpContext.GetIdentityServerIssuerUri();
        var token = new Token(OidcConstants.TokenTypes.AccessToken)
        {
            CreationTime = Clock.UtcNow.UtcDateTime,
            Issuer = issuer,
            Lifetime = request.ValidatedRequest.AccessTokenLifetime,
            Claims = claims.Distinct(new ClaimComparer()).ToList(),
            ClientId = request.ValidatedRequest.Client.ClientId,
            AccessTokenType = request.ValidatedRequest.AccessTokenType
        };

        foreach (var api in request.Resources.ApiResources)
        {
            if (!string.IsNullOrWhiteSpace(api.Name))
            {
                token.Audiences.Add(api.Name);
            }
        }

        return token;
    }
}

And then register CustomTokenService before Identity Configuration

    public void ConfigureServices(IServiceCollection services)
    {
        services.TryAddTransient<ITokenService, CustomTokenService>();

        services.AddDbContext<ApplicationDbContext>(options =>
            options.UseSqlServer(
                Configuration.GetConnectionString("DefaultConnection")));

        services.AddDefaultIdentity<ApplicationUser>()
            .AddEntityFrameworkStores<ApplicationDbContext>();

        services.AddIdentityServer()
            .AddApiAuthorization<ApplicationUser, ApplicationDbContext>();

        services.AddAuthentication()
            .AddIdentityServerJwt();

    }

For a simple way, you could try to override DefaultClaimsService.GetStandardSubjectClaims like

public class CustomClaimsService : DefaultClaimsService
{
    public CustomClaimsService(IProfileService profile
        , ILogger<DefaultClaimsService> logger) : base(profile, logger)
    {
    }
    protected override IEnumerable<Claim> GetStandardSubjectClaims(ClaimsPrincipal subject)
    {
        var claims = base.GetStandardSubjectClaims(subject);
        var newClaims = new List<Claim>(claims)
        {
            new Claim(JwtClaimTypes.Name, subject.Identity.Name)
        };
        return newClaims;
    }
}

And register like

    public void ConfigureServices(IServiceCollection services)
    {
        services.TryAddTransient<IClaimsService, CustomClaimsService>();

        //services.TryAddTransient<ITokenService, CustomTokenService>();

        services.AddDbContext<ApplicationDbContext>(options =>
            options.UseSqlServer(
                Configuration.GetConnectionString("DefaultConnection")));

        services.AddDefaultIdentity<ApplicationUser>()
            .AddEntityFrameworkStores<ApplicationDbContext>();

        services.AddIdentityServer()
            .AddApiAuthorization<ApplicationUser, ApplicationDbContext>();

        services.AddAuthentication()
            .AddIdentityServerJwt();

    }

---

Related Topics