当我使用以下语法删除一行时:

$user->delete();

是否有一种方法来附加一个类型的回调,这样它就会自动这样做:

$this->photo()->delete();

最好是在模型类内部。


当前回答

我在《Laravel 8》中使用了这种方法:

public static function boot() {

    parent::boot();
    
    static::deleted(function($item){
        $item->deleted_by = \Auth::id(); // to know who delete item, you can delete this row
        $item->save();  // to know who delete item, you can delete this row
        foreach ($item->photos as $photo){
            $photo->delete();
        }
    });
}

public function photos()
{
    return $this->hasMany('App\Models\Photos');
}

注意:在此语法中删除$user->photos()->delete();对我没用……

其他回答

注意:这个答案是为Laravel 3编写的。因此,在Laravel的最新版本中可能会或可能不会很好地工作。

在真正删除用户之前,您可以删除所有相关照片。

<?php

class User extends Eloquent
{

    public function photos()
    {
        return $this->has_many('Photo');
    }

    public function delete()
    {
        // delete all related photos 
        $this->photos()->delete();
        // as suggested by Dirk in comment,
        // it's an uglier alternative, but faster
        // Photo::where("user_id", $this->id)->delete()

        // delete the user
        return parent::delete();
    }
}

希望能有所帮助。

我在《Laravel 8》中使用了这种方法:

public static function boot() {

    parent::boot();
    
    static::deleted(function($item){
        $item->deleted_by = \Auth::id(); // to know who delete item, you can delete this row
        $item->save();  // to know who delete item, you can delete this row
        foreach ($item->photos as $photo){
            $photo->delete();
        }
    });
}

public function photos()
{
    return $this->hasMany('App\Models\Photos');
}

注意:在此语法中删除$user->photos()->delete();对我没用……

使用限制()

Laravel 7之后,有了新的foreignId()和constrained()方法来定义数据库中的关系约束。可以在这些方法上使用OnDelete()方法自动删除相关记录。

古老的风格

$table->unsignedBigInterer('user_id');

$table->foreign('user_id')
    ->references('id')
    ->on('users')
    ->onDelete('cascade');

新风格

$table->foreignId('user_id')
      ->constrained()
      ->onDelete('cascade');

在想要删除的模型上添加删除功能 定义模型的关系

例如在这个例子中:

/**
 * @return bool|null
 */
public function delete(): ?bool
{
    $this->profile()->delete();
    $this->userInterests()->delete();
    $this->userActivities()->delete();
    $this->lastLocation()->delete();

    return parent::delete();
}

用户模型中的关系为:

public function profile()
{
    return $this->hasOne(Profile::class, 'user_id', 'id');
}

public function userInterests()
{
    return $this->hasMany(userInterest::class, 'user_id', 'id');
}

public function userActivities()
{
    return $this->hasMany(userActivity::class, 'user_id', 'id');
}

public function lastLocation()
{
    return $this->hasOne(LastLocation::class, 'user_id', 'id');
}

这里有一些完美的解决方案。

# model

public function order_item_properties()
{
    return $this->hasMany(OrderItemProperty::class, 'order_id', 'id');
}

public function order_variations()
{
    return $this->hasMany(OrderItemVariation::class, 'order_id', 'id');
}

# controller

$order_item = OrderItem::find($request->order_id);

$order_item->order_item_properties()->delete();
$order_item->order_variations()->delete();

$order_item->delete();

return response()->json([
    'message' => 'Deleted',
]);