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……

在Laravel 5.2中，文档声明这些类型的事件处理程序应该在AppServiceProvider中注册:

<?php
class AppServiceProvider extends ServiceProvider
{
    /**
     * Bootstrap any application services.
     *
     * @return void
     */
    public function boot()
    {
        User::deleting(function ($user) {
            $user->photos()->delete();
        });
    }

我甚至打算将它们移动到单独的类中，而不是闭包中，以获得更好的应用程序结构。

或者你也可以这样做，只是另一个选择:

try {
    DB::connection()->pdo->beginTransaction();

    $photos = Photo::where('user_id', '=', $user_id)->delete(); // Delete all photos for user
    $user = Geofence::where('id', '=', $user_id)->delete(); // Delete users

    DB::connection()->pdo->commit();

}catch(\Laravel\Database\Exception $e) {
    DB::connection()->pdo->rollBack();
    Log::exception($e);
}

注意，如果你没有使用默认的laravel db连接，那么你需要执行以下操作:

DB::connection('connection_name')->pdo->beginTransaction();
DB::connection('connection_name')->pdo->commit();
DB::connection('connection_name')->pdo->rollBack();

你可以使用这种方法作为替代。

将会发生什么，我们采取与用户表相关联的所有表和删除相关的数据使用循环

$tables = DB::select("
    SELECT
        TABLE_NAME,
        COLUMN_NAME,
        CONSTRAINT_NAME,
        REFERENCED_TABLE_NAME,
        REFERENCED_COLUMN_NAME
    FROM INFORMATION_SCHEMA.KEY_COLUMN_USAGE
    WHERE REFERENCED_TABLE_NAME = 'users'
");

foreach($tables as $table){
    $table_name =  $table->TABLE_NAME;
    $column_name = $table->COLUMN_NAME;

    DB::delete("delete from $table_name where $column_name = ?", [$id]);
}

我相信这是Eloquent事件(http://laravel.com/docs/eloquent#model-events)的一个完美用例。你可以使用"deleting"事件来进行清理:

class User extends Eloquent { public function photos() { return $this->has_many('Photo'); } // this is a recommended way to declare event handlers public static function boot() { parent::boot(); static::deleting(function($user) { // before delete() method call this $user->photos()->delete(); // do the rest of the cleanup... }); } } You should probably also put the whole thing inside a transaction, to ensure the referential integrity..

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');