实体框架6代码优先关系/表创建问题 [英] Entity Framework 6 Code First Relationship/table creation issues

问题描述

我正在尝试进行Code First迁移，但是其中的一个模型/表在迁移时表现得很奇怪。

I'm trying to do a Code First migration, but one of the models/tables behave pretty weird when I migrate.

Team and Tournament制作了一个新表，以引用什么团队属于哪个锦标赛以及相反的方式-这就是我想要的。

Team and Tournament makes a new Table to reference what team belongs to what tournament and the other way around - That's totally what I want.

我正在尝试对Matchup和Team进行相同的操作，为二者都定义了集合，但由于某种原因，它在Matchup中创建了单个属性TeamId，这是一个问题，因为对决应该能够存储多个团队。

I'm trying to do the same with Matchup and Team, defining collections for both, but for some reason it makes a single property, TeamId, in Matchup which is a problem since a Matchup should be able to store more than one Team.

清晰的屏幕截图

预先感谢。

推荐答案

当同一文件中有多个引用时，您需要告诉EF如何建立关系。我更喜欢流利的代码：

You need to tell EF how to do the relationships when you have multiple references in the same file. I prefer fluent code for this:

修复模型：

public class Matchup
{
    public int Id { get; set; }

    public int WinnerId { get; set; }  // FK by convention
    public Team Winner { get; set; }
    public Tournament Tournament { get; set; }
    public ICollection<Team> Teams { get; set; }
}

public class Team
{
    public int Id { get; set; }

    public ICollection<Player> Players{ get; set; }
    public ICollection<Matchup> Matchups{ get; set; }
    public ICollection<Matchup> MatchupWinners{ get; set; }
    public ICollection<Tournament> Tournaments{ get; set; }
}


// Configure 1 to many
modelBuilder.Entity<Matchup>()
    .HasOptional(m => m.Winner)
    .WithMany(p => p.MatchupWinners)
    .HasForeignKey(p => p.WinnerId);

// Configure many to many
modelBuilder.Entity<Matchup>()
        .HasMany(s => s.Teams)
        .WithMany(c => c.Matchups)
        .Map(t =>
                {
                    t.MapLeftKey("MatchupId");
                    t.MapRightKey("TeamId");
                    t.ToTable("MatchupTeam");
                });

但是您也可以使用注释：

But you can also do it with annotations:

public class Team
{
    public int Id { get; set; }

    public ICollection<Player> Players{ get; set; }

    [InverseProperty("Teams")]
    public ICollection<Matchup> Matchups{ get; set; }

    [InverseProperty("Winner")]
    public ICollection<Matchup> MatchupWinners{ get; set; }

    public ICollection<Tournament> Tournaments{ get; set; }
}

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