laravel - (Laravel) 通过数据透视表的多态关系

Question

比方说，我有一个 Event 模型，它通过多态关系和一个数据透视表(EventParticipant)有更多的各种模型(Player、Coach、Admin)的参与者，其中还包含一个 bool 列 participate .我想通过 $event->participants 获取参与者，它通过多态关系检索球员、教练和管理员的集合。

我在训练中使用标准非多态关系创建了类似的东西，如下所示:

class Training extends Model
{
    /**
    * Training has more players.
    */
    public function players() {
        return $this->belongsToMany('App\Player', 'training_player')
            ->using('App\TrainingPlayer')
            ->withPivot('participate');
    }
}

class TrainingPlayer extends Pivot
{
    /**
     * The attributes that should be cast to native types.
     *
     * @var array
     */
    protected $casts = [
        'participate' => 'boolean'
    ];
}

在事件的情况下如何修改， 参与者()可以是 Player、Coach 或 Admin 模型？ (也许与 MorphPivot 类有关，但我无法想象如何。)

(而不是 player_id(在 TrainingPlayer 类中)指的是 Player 模型的 id，有两列 role 和 rollable_id(在 EventParticipant 类中)，它们指的是 Player、Coach、或管理模型，分别)

class Event extends Model
{
    /**
    * Event has more participants (players, coaches, or admins).
    */
    public function participants() {
        //
    }
}

class EventParticipant extends MorphPivot
{
    //
}

任何帮助将不胜感激。 :) 谢谢

Answer 1

我一直在寻找类似的东西并想出了一个解决方案。根据 Jonas 的评论，您不能在 1 个相关集中有不同的模型，但您可以使用 1 个数据透视表为每个模型设置 1 个。
您现在可以使用 \App\Team::find(1)->with(['managers', 'users'])->get(); 查询此信息

Schema::create('associations', function (Blueprint $table) {
    $table->id();
    $table->string('association_type');
    $table->integer('association_id');
    $table->integer('team_id');
    $table->integer('meta')->nullable();
    $table->timestamps();
});

Schema::create('managers', function (Blueprint $table) {
    $table->id();
    $table->timestamps();
});

Schema::create('users', function (Blueprint $table) {
    $table->id();
    $table->timestamps();
});

Schema::create('teams', function (Blueprint $table) {
    $table->id();
    $table->timestamps();
});

class Manager extends Model
{
    public function teams()
    {
        return $this->belongsToMany('\App\Team', 'associations')->using('App\Association');
    }
}

class Team extends Model
{
    public function managers()
    {
        return $this->morphedByMany('App\Manager', 'association')->using('App\Association');
    }

    public function users()
    {
        return $this->morphedByMany('App\User', 'association')->using('App\Association');
    }
}

class User extends Authenticatable
{
    public function teams()
    {
        return $this->belongsToMany('\App\Team', 'associations')->using('App\Association');
    }
}

// App/Association
use Illuminate\Database\Eloquent\Relations\MorphPivot;

class Association extends MorphPivot
{
    protected $table = 'associations';  // not sure if this is needed
}