Laravel插入数据透视表

Question

我正在尝试将数据写入数据透视表，但是得到“在null上调用成员函数guest（）的成员”

这是我的代码，我哪里出问题了？

我已经尝试过了，对什么错我感到困惑

事件模型

    <?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Event extends Model
{

    /**
     * The table associated with the model.
     *
     * @var string
     */
    protected $table = 'events';

    /**
     * The attributes that are mass assignable.
     *
     * @var array
     */
    protected $fillable = ['headline', 'description', 'address', 'zip', 'longitude', 'latitude',
        'position', 'country_id', 'cat_id', 'start_date', 'end_date'];

    public function user()
    {
        return $this->belongsTo('App\User');
    }

    /**
     * The products that belong to the shop.
     */
    public function guests()
    {
        return $this->belongsToMany('App\Models\Guest', 'event_guest', 'guest_id', 'event_id');
    }
}

访客模型

     <?php

namespace App\Models;

    use Illuminate\Database\Eloquent\Model;
class Guest extends Model
{

 protected $fillable = ['first_name', 'last_name', 'email'];
public function events()
{
    return $this->belongsToMany('App\Models\Event', 'event_guest', 'event_id', 'guest_id');
}
}

控制者

 //RSVP events
public function rsvpCheck()
{
    $check = Guest::find(5);
    //$guestCheck = Event::where('id',5)->first();

    $check->events()->attach(2);

    return $check->events;
}

Answer 1

尝试以这种方式进行。 将此添加到您的create_events_migration下面

   Schema::create('event_guest', function (Blueprint $table) {
       $table->integer('event_id')->unsigned()->index();
       $table->foreign('event_id')->references('id')->on('events');
       $table->integer('guest_id')->unsigned()->index();
       $table->foreign('guest_id')->references('id')->on('guests');
    });

在您的事件模型中使用此关系

public function guests()
    {
        return $this->belongsToMany(Guest::class); // include at the top:  use App\Models\Guest;
    }

在您的访客模型中

public function events()
        {
            return $this->belongsToMany(Event::class); // include at the top:  use App\Models\Event;
        }

在您的数据库中添加一些虚拟数据（事件和来宾之间的关系）并将此代码粘贴到您的路由中

Route::get('/testguest', function(){

            $guest= Guest::first();
            dd($company->events);

        });

反之亦然

路线：： get（'/ testevents'，function（）{

            $event= Event::first();
            dd($event->guests);

        });

让我知道您到目前为止是否可以正常使用并获得了虚拟数据

Answer 2

按照@Mike的建议更改您的关系方法。

如下更改事件模型中的guests()方法：

public function guests()
    {
        return $this->belongsToMany('App\Models\Guest');
    }

如下更改客户模型中的events()方法：

public function events()
{
    return $this->belongsToMany('App\Models\Event');
}

现在，要将数据插入数据透视表，您有两种情况：
1）没有数据

public function rsvpCheck()
{
    $check = Guest::findOrFail(5);
    $check->events()->attach(2);
    return $check->events();
}

2）需要在数据透视表中插入额外的数据

public function rsvpCheck()
{
    $data = ['attribute'=>'value'];//replace this with the data you want to insert 
    $check = Guest::findOrFail(5);
    $check->events()->attach(2,$data);
    return $check->events();
}