ApplicationParts.Controllers.ManageController.LinkLoginCallback C# (CSharp) Метод

        public async Task<ActionResult> LinkLoginCallback()
        {
            var user = await GetCurrentUserAsync();
            if (user == null)
            {
                return View("Error");
            }
            var info = await _signInManager.GetExternalLoginInfoAsync(await _userManager.GetUserIdAsync(user));
            if (info == null)
            {
                return RedirectToAction(nameof(ManageLogins), new { Message = ManageMessageId.Error });
            }
            var result = await _userManager.AddLoginAsync(user, info);
            var message = result.Succeeded ? ManageMessageId.AddLoginSuccess : ManageMessageId.Error;
            return RedirectToAction(nameof(ManageLogins), new { Message = message });
        }