我怎样才能在 Laravel 中获得我的关系的支点？

Question

我在我的应用程序中有一个关系。 一个候选人可以有多个“candidate_trainings”，每个“candidate_training”都与一个训练相关联。 我想避免将“candidate_trainings”作为中心点，因为在分离时很难删除正确的值，等等。所以，我如何才能在我的 hasMany 关系中使用来自 Training 模型的数据获取 CandidateTraining 模型。

以下是我的关系：

<?php

namespace App;

use App\Traits\SanitizeIds;
use App\Salary;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Support\Facades\Storage;

class Candidate extends Model
{

    public function saveTraining($data) {
        $this->candidateTrainings()->delete();
        foreach(json_decode($data['training']) as $training) {
            if(Training::find($training->training)->first()) {
                $candidateTraining = new CandidateTraining;
                $candidateTraining->description = $training->value;
                $candidateTraining->training_id = $training->training;
                $this->candidateTrainings()->save($candidateTraining);
            }
        }
    }


    public function candidateTrainings() {
        return $this->hasMany('\App\CandidateTraining');
    }

    public function trainings() {
        return $this->belongsToMany('\App\Training');
    }

}

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Training extends Model
{
    protected $fillable = ['name_french', 'name_english'];

    public function candidates() {
        return $this->belongsToMany('\App\Candidate');
    }

    public function candidateTrainings() {
        return $this->hasMany('\App\CandidateTraining');
    }
}

<?php

namespace App;

use Illuminate\Database\Eloquent\Relations\Pivot;

class CandidateTraining extends Pivot
{
    public function candidate() {
        return $this->belongsTo('\App\Candidate');
    }

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

谢谢！

Answer 1

为了能够直接在CandidateTraining模型上更新数据，您需要向其中添加$fillable字段。

protected $fillable = ['training_id', 'description'];

您的代码应该可以工作！ 但如果你不介意，我做了一点重构。 您可以通过另一种方式完成此操作：

<?php

namespace App;

use App\Traits\SanitizeIds;
use App\Salary;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Support\Facades\Storage;

class Candidate extends Model
{
    public function saveTraining($data)
    {
        // remove all relationships
        $this->trainings()->detach();

        // add new ones
        foreach(json_decode($data['training']) as $training)
        {
            if(Training::find($training->training)->first())
            {
                $this->trainings()->attach($training->training, [
                    'description' => $training->value,
                ]);
            }
        }
    }

    public function candidateTrainings()
    {
        return $this->hasMany(App\CandidateTraining::class);
    }

    public function trainings()
    {
        return $this->belongsToMany(App\Training::class)
            ->withTimestamps()
            ->using(App\CandidateTraining::class)
            ->withPivot([
                'id',
                'training_id',
                'description',
            ]);
    }
}

那个$training->training东西是不可读的，如果可以的话，把它改成$training->id类的东西。

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Training extends Model
{
    protected $fillable = ['name_french', 'name_english'];

    public function candidates()
    {
        return $this->belongsToMany(App\Candidate::class)
            ->withTimestamps()
            ->using(App\CandidateTraining::class)
            ->withPivot([
                'id',
                'training_id',
                'description',
            ]);;
    }

    public function candidateTrainings()
    {
        return $this->hasMany(App\CandidateTraining::class);
    }
}

<?php

namespace App;

use Illuminate\Database\Eloquent\Relations\Pivot;

class CandidateTraining extends Pivot
{
    protected $fillable = ['training_id', 'description'];

    public function candidate()
    {
        return $this->belongsTo(App\Candidate::class);
    }

    public function training()
    {
        return $this->belongsTo(App\Training::class);
    }
}

如果要从控制器访问枢轴对象：

$candidates = Candidate::with(['trainings'])->get();
foreach ($candidates as $candidate)
{
    dd($candidate->pivot);
}