我無法從Identity擴展屬性。這樣做的全部原因是使我的員工數據庫與應用程序數據庫（包括身份信息）集成在一起，并將其用作一個大型數據庫。我嘗試遵循此答案，但似乎他們正在使用另一版本的ASP.NET。我正在使用ASP.NET Core，版本：2.0.3這是我ApplicationUser.cs文件的代碼using System;using System.Collections.Generic;using System.Linq;using System.Security.Claims;using System.Threading.Tasks;using Microsoft.AspNetCore.Identity;namespace src.Models{    public class ApplicationUser : IdentityUser    {        public async Task<ClaimsIdentity> GenerateUserIdentityAsync(UserManager<ApplicationUser> manager) {            var userIdentity = await manager.CreateIdentityAsync(this, DefaultAuthenticationTypes.ApplicationCookie);            userIdentity.AddClaim(new Claim("FirstName", this.FirstName.ToString()));            userIdentity.AddClaim(new Claim("LastName", this.LastName.ToString()));            userIdentity.AddClaim(new Claim("JobTitle", this.JobTitle.ToString()));            userIdentity.AddClaim(new Claim("Status", this.Status.ToString()));            return userIdentity;        }        string FirstName { get; set; }        string LastName { get; set; }        string JobTitle { get; set; }        string Status { get; set; }        int Age { get; set; }    }}我在出現錯誤CreateIdentityAsync，并顯示以下錯誤：'UserManager<ApplicationUser>' does not contain a definition for 'CreateIdentityAsync' and no extension method 'CreateIdentityAsync' accepting a first argument of type 'UserManager<ApplicationUser>' could be found (are you missing a using directive or an assembly reference?) [src]和上的錯誤DefaultAuthenticationTypes，錯誤：The name 'DefaultAuthenticationTypes' does not exist in the current context [src]使用ASP.NET Core無法做到這一點，還是我做錯了什么？