每当laravel中发生记录插入或更新时，在数据透视表中设置一个字段

<?php

namespace App\Observers;

use App\Models\User;
use App\Models\PivotTable;

class UserObserver
{
    public function created(User $user)
    {
        // 在记录插入时执行的操作
        $pivotTable = new PivotTable();
        $pivotTable->user_id = $user->id;
        $pivotTable->field = 'value';
        $pivotTable->save();
    }

    public function updated(User $user)
    {
        // 在记录更新时执行的操作
        $pivotTable = PivotTable::where('user_id', $user->id)->first();
        if ($pivotTable) {
            $pivotTable->field = 'new value';
            $pivotTable->save();
        }
    }
}

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use App\Observers\UserObserver;

class User extends Model
{
    protected static function boot()
    {
        parent::boot();

        static::observe(UserObserver::class);
    }
}