ASP.NET Core 延迟加载始终返回 null

我是第一次使用ASP.NET Core，我正在try 创建一个API.我有一个问题，当我试图返回一个城市的用户使用懒惰加载代理程序包.有谁能帮帮我吗？谢谢你的帮助.

这是我的dbcontext配置

services.AddDbContext<ApplicationDbContext>(option =>
        {
            option.UseLazyLoadingProxies()                
            .UseSqlServer(configuration.GetConnectionString("DefaultConnection"));
            option.LogTo(Console.WriteLine,LogLevel.Information);
            option.EnableSensitiveDataLogging();                                
        });
        

这是我的User个实体:

using ecommerce.Domain.Abstract;
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using tables.Base.Entity;

namespace ecommerce.Domain.Entities
{
    public class User : BaseEntity
    {
        public Guid Id { get; set; }

        public Guid CityId { get; set; }
        public virtual City City { get; set; }

        public string Name { get; set; }
         
        [Range(0,Double.MaxValue)]
        public int Point { get; set; }

        public Guid AccountId { get; set; } 
        public virtual Account Account { get; set; }
        
        public bool IsBlocked { get; set; }
    }
}

这是我对City实体的配置:

using ecommerce.Domain.Entities;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata.Builders;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ecommerce.infrutructure.Configuration
{
    internal class CityConfigration : IEntityTypeConfiguration<City>
    {
        public void Configure(EntityTypeBuilder<City> builder)
        {
            builder.Property(c => c.Delivery_Price).HasDefaultValue(0);
            builder.Property(c=>c.status).HasDefaultValue(false);
            builder.HasMany(c => c.Users)
                   .WithOne(u => u.City);
        }
    }
}

在这里，user.city在返回中为空

public async Task<OperationResultBase<UserWithToken>> Handle(AddUserCommand request, CancellationToken cancellationToken)
{
    var Account = mapper.Map<Account>(request);
    var Accountresult = await this.userManager.CreateAsync(Account, request.Password);
    this.DbContext.SaveChanges();

    if (!Accountresult.Succeeded)
    {
        throw new CanotCreateAccountException(Accountresult.Errors);
    }

    var User = mapper.Map<User>(request, opts => opts.AfterMap((src, desc) => desc.AccountId = Account.Id));            

    this.DbContext.Users.Add(User);
    this.DbContext.SaveChanges();

    TokenDto TokenInfo = jwtRepository.GetTokens(Account);
    UserWithToken result = new UserWithToken()
        {
            Id = User.Id,
            Name = User.Name,
            UserName = User.Account.UserName,
            City = User.City,
            Email = User.Account.Email,
            IsBlocked = User.IsBlocked,
            Point = User.Point,   
            TokenInfo = TokenInfo
        };

    return Created<UserWithToken>(result, "The user was created successfully");
}