Question

在多租户应用程序中，我们可以强制下拉列表中另一个租户的ID，例如

我的模特是：

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.5.6.RELEASE</version>
    <relativePath /> <!-- lookup parent from repository -->
</parent>

此代码应生成类似于此的表：

public class Tenant
{
    public int Id { get; set; }
    public string Name { get; set; }
}
public class Customer
{
    public int Id { get; set; }
    public int TenantId { get; set; }
    public string Name { get; set;}
}
public class Order
{
    public int Id { get; set; }
    public int CustomerId { get; set; }
    public int TenantId { get; set; }

    public float Price { get; set; }
}

但是，如何使用 FLUENT API 创建合成？

修改我想确保传递给Order.cs的CustomerID具有相同的TenantId

也就是说，客户和订单必须具有相同的TenantId

Answer 1

我想确保传递给Order.cs的CustomerID具有相同的TenantId

在Fludent API中声明复合外键就像声明复合主键一样。使用匿名类型。

using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations.Schema;
using System.Data.Entity;
using System.Data.Entity.ModelConfiguration;
using System.Data.SqlClient;
using System.Linq;

namespace ConsoleApp8
{

    public class Tenant
    {
        public int Id { get; set; }
        public string Name { get; set; }
    }
    public class Customer
    {
        public int Id { get; set; }
        public int TenantId { get; set; }
        public virtual Tenant Tenant {get;set;}
        public string Name { get; set; }
    }
    public class Order
    {
        public int Id { get; set; }
        public int CustomerId { get; set; }
        public int TenantId { get; set; }

        public Customer Customer { get; set; }
        public Tenant Tenant { get; set; }

        public decimal Price { get; set; }
    }

    class Db : DbContext
    {


        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {

            modelBuilder.Entity<Tenant>().HasKey(e => e.Id);
            modelBuilder.Entity<Customer>().HasKey(e => new { e.TenantId, e.Id });
            modelBuilder.Entity<Order>().HasKey(e => new { e.TenantId, e.CustomerId, e.Id });

            modelBuilder.Entity<Customer>()
                        .HasRequired<Tenant>(e => e.Tenant)
                        .WithMany()
                        .HasForeignKey(e => e.TenantId);

            modelBuilder.Entity<Order>()
                        .HasRequired<Customer>(e => e.Customer)
                        .WithMany()
                        .HasForeignKey(e => new { e.TenantId, e.CustomerId });

            modelBuilder.Entity<Order>()
                        .HasRequired<Tenant>(e => e.Tenant)
                        .WithMany()
                        .HasForeignKey(e => e.TenantId)
                        .WillCascadeOnDelete(false);

        }
    }



    class Program
    {      

        static void Main(string[] args)
        {

            Database.SetInitializer(new DropCreateDatabaseAlways<Db>());

            using (var db = new Db())
            {
                db.Database.Log = m => Console.WriteLine(m);

                db.Database.Initialize(true);






            }


            Console.WriteLine("Hit any key to exit");
            Console.ReadKey();


        }
    }
}

使用实体框架在多个外键中创建组合

1 个答案: