Entity framework核心一对一

Question

The databse

(Project,Contest,LocalJob)->每个都有1个WorkDetails，1个WorkDetails有其中之一

你好，这是我的数据库，我想问你以下问题：

我应该在 WorkDetails 中为项目、竞赛或 LocalJobs 添加外键列吗？

如果我必须如何实现导航属性？

Answer 1

在代码优先中，您可以为此使用自有类型：

using Microsoft.EntityFrameworkCore;
using System.Linq;
using System;
using System.ComponentModel.DataAnnotations.Schema;
using System.Collections.Generic;

namespace efCoreTest
{

    class Project
    {
        public int Id { get; set; }
        public WorkDetail WorkDetail { get; set; }

    }
    class Contest
    {
        public int Id { get; set; }
        public WorkDetail WorkDetail { get; set; }
    }
    class LocalJob
    {
        public int Id { get; set; }
        public WorkDetail WorkDetail { get; set; }
    }
    class WorkDetail
    {
        public int Id { get; set; }
        public DateTime StartDate { get; set; }
        public DateTime EndDate { get; set; }
    }
    class Db : DbContext
    {
        public DbSet<Project> Projects { get; set; }
        public DbSet<Contest> Contests { get; set; }
        public DbSet<LocalJob> LocalJobs { get; set; }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            optionsBuilder.UseSqlServer("Server=.;Database=efCoreTest;Integrated Security=true");
        }
        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.Entity<Project>().OwnsOne(p => p.WorkDetail);
            modelBuilder.Entity<Contest>().OwnsOne(p => p.WorkDetail);
            modelBuilder.Entity<LocalJob>().OwnsOne(p => p.WorkDetail);



            base.OnModelCreating(modelBuilder);
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            using (var db = new Db())
            {
                db.Database.EnsureDeleted();
                db.Database.EnsureCreated();


            }

        }
    }
}

Entity framework核心一对一

Entity framework core One to One

entity-framework

ef-core-2.0