实体框架代码优先映射

本文介绍了实体框架代码优先映射的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我有两个班，组类有许多与用户类（表示用户所属的组）的组，然后也有一对多的用户类的关系（占所有者一对多的关系一组）。

I have two classes, the Group class has a many to many relationship with the User class (representing the groups a user belongs to) and then the group also has a relationship of one to many with the user class (representing the owner of a group).

我该如何映射呢？

public class User { public int Id { get; set; } public string Avatar { get; set; } public string Name { get; set; } public string Message { get; set; } public virtual ICollection<Group> OwnedGroups { get; set; } public virtual ICollection<Group> Groups { get; set; } } public class Group { public int Id { get; set; } public DateTime CreateDate { get; set; } public DateTime ModifyDate { get; set; } public string Name { get; set; } public string Description { get; set; } public bool System { get; set; } public int ViewPolicy { get; set; } public int JoinPolicy { get; set; } public string Avatar { get; set; } public int Order { get; set; } public int GroupType { get; set; } public virtual User Owner { get; set; } public virtual ICollection<User> Members { get; set; } }

TKS提前！

tks in advance!

推荐答案

我会用流利的API：

public class Context : DbContext { public DbSet<User> Users { get; set; } public DbSet<Group> Groups { get; set; } protected override void OnModelCreating(DbModelBuilder modelBuilder) { base.OnModelCreating(modelBuilder); modelBuilder.Entity<User>() .HasMany(u => u.Groups) .WithMany(g => g.Members); modelBuilder.Entity<User>() .HasMany(u => u.OwnedGroups) .WithRequired(g => g.Owner) .WillCascadeOnDelete(false); } }

还应该有可能与数据的注解：

It should also be possible with Data annotations:

public class User { ... [InverseProperty("Owner")] public virtual ICollection<Group> OwnedGroups { get; set; } [InverseProperty("Members")] public virtual ICollection<Group> Groups { get; set; } } public class Group { ... [InverseProperty("OwnedGroups")] public virtual User Owner { get; set; } [InverseProperty("Groups")] public virtual ICollection<User> Members { get; set; } }

InverseProperty 是无需对关系的两侧，但它确实定义清晰。

InverseProperty is not needed on both sides of relation but it does definition clearer.