属性已经存在，无法添加？

Question

我在程序包管理器控制台中的错误：

The property or navigation 'MenuId' cannot be added to the entity type 'ThAmCo.Catering.Models.FoodBooking' because a property or navigation with the same name already exists on entity type 'ThAmCo.Catering.Models.FoodBooking'.

我正在尝试为作业创建数据库，但是，我遇到了这个错误。

这是我当前的 DbContext：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;

namespace ThAmCo.Catering.Models
{
    public class ThAmCoContext : DbContext
    {
        public DbSet<MenuFoodItem> MenuFoodItem { get; set; }
        public DbSet<FoodBooking > FoodBooking { get; set; }
        public DbSet<Menu> Menu { get; set; }
        public DbSet<FoodItem> FoodItem { get; set; }

        protected override void OnConfiguring(DbContextOptionsBuilder options) =>
            options.UseSqlServer(@"Server=(localdb)\mssqllocaldb;Database=ThAmCoCatering;");

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

            // Foreign Key
            builder.Entity<MenuFoodItem>()
                .HasKey(a => new { a.MenuId, a.FoodItemId });

            builder.Entity<MenuFoodItem>()
              .HasOne(a => a.Menu)
              .WithMany(m => m.FoodItem)
              .HasForeignKey(a => a.MenuId)
              .HasForeignKey(a => a.FoodItemId);

            builder.Entity<MenuFoodItem>()
               .HasOne(a => a.FoodItem)
               .WithMany()
               .HasForeignKey(a => a.FoodItemId);

            builder.Entity<FoodBooking>()
                .HasOne(m => m.Menu)
                .WithMany()
                .HasForeignKey(m => m.MenuId)
                .OnDelete(DeleteBehavior.Restrict);

            builder.Entity<FoodBooking>()
               .HasOne(a => a.Menu)
               .WithMany()
               .HasForeignKey(a => a.MenuId);
        }
    }
    }

这是我的美食预订：

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Threading.Tasks;

namespace ThAmCo.Catering.Models
{
    public class FoodBooking
    {
        public FoodBooking()
        {


        }

        [Key]
        public int FoodBookingId { get; set; }

        
        public int ClientReferenceId { get; set; }
        
        public int NumberOfGuests { get; set; }

        public Menu Menu { get; set; }
        public int MenuId { get; set; }
        
    }

}

这是我的 FoodItem class:

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Threading.Tasks;

namespace ThAmCo.Catering.Models
{
    public class FoodItem
    {
        public FoodItem()
        {
        }

        public FoodItem(int FoodItemId, string Description, float UnitPrice)
        {
            this.FoodItemId = FoodItemId;
            this.Description = Description;
            this.UnitPrice = UnitPrice;
        }

        public int FoodItemId { get; set; }

        [Required]
        public string Description { get; set; }

        [Required]
        public float UnitPrice { get; set; }


    }
}

这是我的菜单class:

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Threading.Tasks;

namespace ThAmCo.Catering.Models
{
    public class Menu
    {
        public Menu()
        {

        }


        public Menu(int MenuId, string MenuName)
        {

        }

        [Key]
        public int MenuId { get; set; }

        [Required]
        public string MenuName { get; set; }

        public ICollection<MenuFoodItem> FoodItem { get; set; }

    }
}

这是我的 MenuFoodItem class:

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Threading.Tasks;

namespace ThAmCo.Catering.Models
{
    public class MenuFoodItem
    {

        public MenuFoodItem()
        {

        }
        
        public MenuFoodItem(int FoodItemId, int MenuId)
        {
            this.FoodItemId = FoodItemId;
            this.MenuId = MenuId;
        }



       
        public int FoodItemId { get; set; }
        public FoodItem FoodItem { get; set; }
        
        public int MenuId { get; set; }
        public Menu Menu { get; set; }

        
    }
}

就上下文而言，它应该是一个网络应用程序，它允许我为一个场所创建菜单和食品。

根据规范，ERD 应如下所示：

Answer 1

删除这个重复的部分：

builder.Entity<FoodBooking>()
.HasOne(a => a.Menu)
.WithMany()
.HasForeignKey(a => a.MenuId);

更新这部分：

builder.Entity<MenuFoodItem>() 
.HasOne(a => a.Menu)
.WithMany(m => m.FoodItem)
.HasForeignKey(a => a.MenuId)
.HasForeignKey(a => a.FoodItemId); 

builder.Entity<MenuFoodItem>()
.HasOne(a => a.FoodItem)
.WithMany()
.HasForeignKey(a => a.FoodItemId);

至

builder.Entity<MenuFoodItem>()
.HasOne(a => a.FoodItem)
.WithMany()
.HasForeignKey(a => a.FoodItemId);

builder.Entity<MenuFoodItem>()
.HasOne(a => a.Menu)
.WithMany(a => a.FoodItem)
.HasForeignKey(a => a.MenuId);

属性已经存在，无法添加？

Property cannot be added as it already exists?

c#

entity-framework

entity-framework-core

属性 已经存在，无法添加？

Property cannot be added as it already exists?

c#

entity-framework

entity-framework-core

属性已经存在，无法添加？