EF Core子表多个外键关连同一主表设置方法

 当子表的多个外键关连同一主表时，EF Core模型应该如何配置呢？

例：记录一条销售单信息，需要保存销售员、和制单人（记录的操作人），而这两个字段都需要指向User表。

销售单表（子表）B01_SO模型类如下：

using System;using System.Collections.Generic;using System.Linq;using System.Threading.Tasks;using System.ComponentModel.DataAnnotations;namespace Test.Models{ public class B01_SO {  [Key]  public int ID { get; set; }  [Display(Name ="销售单号")]  [StringLength(50)]  [Required]  public string SONum { get; set; }  [Display(Name = "单据编号")]  [StringLength(50)]    public string TKNum { get; set; }  [Display(Name = "交期")]  [Required]  public DateTime Dtime { get; set; }  [Display(Name = "产品描述")]  [StringLength(200)]  [Required]  public string Description { get; set; }  [Display(Name = "销售员")]  public int? SaleID { get; set; }  [Display(Name = "销售员")]  public User Sales { get; set; }  [Display(Name = "制单人")]    public int? UserID { get; set; }  [Display(Name = "制单人")]  public User User { get; set; } }}

User表（主表）模型类如下：

using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.ComponentModel.DataAnnotations;using System.ComponentModel.DataAnnotations.Schema;namespace Test.Models{ public class User {  [Key]  public int ID { get; set; }  [Display(Name = "用户名")]  [StringLength(50)]  [Required]  public string Name { get; set; }  [Display(Name = "邮箱")]  [StringLength(100)]  [Required]  public string Email { get; set; }  [Display(Name = "密码")]  [StringLength(50)]  [Required]  public string Password { get; set; }  [Display(Name = "是否启用")]  [Required]  public bool Enabled { get; set; }  [Display(Name = "性别")]  [StringLength(10)]  [Required]  public string Gender { get; set; }  [Display(Name = "中文名")]  [StringLength(100)]  public string ChineseName { get; set; }  [Display(Name = "英文名")]  [StringLength(100)]  public string EnglishName { get; set; }  [Display(Name = "照片")]  [StringLength(200)]  public string Photo { get; set; }  [Display(Name = "QQ")]  [StringLength(50)]  public string QQ { get; set; }  [Display(Name = "公司邮箱")]  [StringLength(100)]  public string CompanyEmail { get; set; }  [Display(Name = "工作电话")]  [StringLength(50)]  public string OfficePhone { get; set; }  [Display(Name = "分机号")]  [StringLength(50)]  public string OfficePhoneExt { get; set; }  [Display(Name = "家庭电话")]  [StringLength(50)]  public string HomePhone { get; set; }  [Display(Name = "手机号")]  [StringLength(50)]  public string CellPhone { get; set; }  [Display(Name = "地址")]  [StringLength(500)]  public string Address { get; set; }  [Display(Name = "备注")]  [StringLength(500)]  public string Remark { get; set; }  [Display(Name = "身份证")]  [StringLength(50)]  public string IdentityCard { get; set; }  [Display(Name = "生日")]  public DateTime? Birthday { get; set; }  [Display(Name = "任职时间")]  public DateTime? TakeOfficeTime { get; set; }  [Display(Name = "上次登录时间")]  public DateTime? LastLoginTime { get; set; }  [Display(Name = "创建时间")]  public DateTime? CreateTime { get; set; }    public ICollection<B01_SO> SalseB01_SOs { get; set; }  public ICollection<B01_SO> UserB01_SOs { get; set; } } }

Fluent  API 配置：

using System;using System.Collections.Generic;using System.Linq;using System.Web;using Microsoft.EntityFrameworkCore;using Microsoft.Extensions.Logging;namespace TestCore.Models{ public class TestCoreContext : DbContext {  #region 启用控制台日志 EF Core  public static readonly ILoggerFactory MyLoggerFactory = LoggerFactory.Create(builder => { builder.AddConsole(); });  protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)   => optionsBuilder    .UseLoggerFactory(MyLoggerFactory);