Question

我一直试图找到最适合我的问题的解决方案，而没有得到我想要的。

我现在有4张桌子，结构看起来像这样。

:: Users ::
id
name
email
------

:: user_equipment ::
id
user_id
equipment_id
equipment_type

:: weapons ::
id
name
price

:: armor ::
id
name
price

我的目标是能够像这样使用我的关系：

$user->equipment
$user->equipment->weapons
$user->equipment->armor

这是我现在拥有的：

用户模型：

class User extends Model
{    
  public function equipment()
  {
    return $this->hasOne(UserEquipment::class);
  }
}

用户设备模型：

class UserEquipment extends Model
{
   public function weapons()
   {
     return $this->hasMany(Weapon::class);
   }
}

Answer 1

首先，您的User模型和UserEquipment模型具有相同的类名。

尝试一下，将您的user模型更改为

public function weapons()
{
    return $this->hasMany('App\Weapon', 'equipment_id')->where('equipment_type','weapon'); //second paramater tells what column to relate the id
} 

public function armors()
{
    return $this->hasMany('App\Armors', 'equipment_id')->where('equipment_type','armor'); 
}

然后是您的查询方式：

User::with('weapons', 'armors')->get();

Answer 2

在我看来，这就像Many To Many Polymorphic Relationship。

在您的情况下，您需要通过以下方式定义您的关系：

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class User extends Model
{
    /**
     * Get all of the weapons owned by the user.
     */
    public function weapons()
    {
        return $this->morphedByMany('App\Weapon', 'equipment', 'user_equipment');
    }

    /**
     * Get all of the armors owned by the user.
     */
    public function armors()
    {
        return $this->morphedByMany('App\Armor', 'equipment', 'user_equipment');
    }
}

进行查询：

$user = App\User::find(1);

foreach ($user->weapons as $weapon) {
    //
}

foreach ($user->armors as $armor) {
    //
}

Answer 3

尝试像这样更改表格：

:: Users ::
id
name
email
------

:: user_equipment ::
id
user_id
equipment_type

:: weapons ::
id
name
price
user_equipment_id

:: armor ::
id
name
price
user_equipment_id

然后，您可以像使用它们一样使用这些功能：用户模型：

class User extends Model
{    
  public function equipment()
  {
    return $this->hasOne(UserEquipment::class);
  }
}

用户设备模型：

class UserEquipment extends Model
{
   public function weapons()
   {
     return $this->hasMany(Weapon::class);
   }
   public function armor()
   {
     return $this->hasMany(Armor::class);
   }
}

laravel中的注意事项Laravel在模型Weapons中假定存在外键调用user_equipment_id： https://laravel.com/docs/5.7/eloquent-relationships#one-to-many

Laravel与类型的关系

3 个答案: