Entity Framework Core 双向关系

问题描述

如何使双向关系在 Entity Framework Core 中工作？

• 做.net 6
• 英孚核心 6.0.13

public class User
{
    public int id { get; set; }
    public string username { get; set; }

    public Department Department{ get; set; }
    public int DepartmentId { get; set; }
}

public class Department
{
    public int Id { get; set; }
    public string Name { get; set; }

    public User? Manager { get; set; }
    public int? ManagerId { get; set; }
    public ICollection<AppUser> Users { get; set; }
}

数据库上下文 class

public DbSet<User> Users { get; set; }
public DbSet<Department> Departments { get; set; }

protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);

            modelBuilder.Entity<Department>()
                        .HasOne(d => d.Manager)
                        .WithOne(u => u.Department)
                        .HasForeignKey<Department>(d => d.ManagerId);

            modelBuilder.Entity<AppUser>()
                        .HasOne(u => u.Department)
                        .WithMany(d => d.Users)
                        .HasForeignKey(user => user.DepartmentId);


            modelBuilder.SeedDepartments();
        }

迁移错误

无法在“Department.Users”和“AppUser.Department”之间创建关系，因为“Department.Manager”和“AppUser.Department”之间已经存在关系。 导航只能参与单一关系。 如果您想首先在“OnModelCreating”中覆盖导航“AppUser.Department”上的现有关系调用“忽略”