通过 N 个模型的 hasMany 或 hasManyThrough 链

Question

如何获取属于特定用户的所有提交？试试这个：

$user=User::find(1);        
dd($user->submissions);

抛出错误：

Call to undefined method Illuminate\Database\Query\Builder::hasMany()

我必须循环遍历模型吗？

以下是模型：

class User extends Eloquent implements ConfideUserInterface, BillableInterface
{
    public function categories()
    {
        return $this->hasMany('Category');
    }
    public function forms()
    {
        return $this->hasManyThrough('App\Models\Form', 'Category');
    }

    public function submissions()
    {
        return $this->hasMany('Category')->hasMany('Form')->hasMany('Submission');
    }
}

class Category extends \Eloquent {
    public function user()
    {
        return $this->belongsTo('User');
    }
    public function forms()
    {
        return $this->hasMany('App\Models\Form');
    }
    public function submissions()
    {
        return $this->hasManyThrough('Submission', 'App\Models\Form', 'id', 'form_id');
    }
}

namespace App\Models;

class Form extends \Eloquent {
    public function user()
    {
        return $this->category->user();
    }
    public function category()
    {
        return $this->belongsTo('Category');
    }
    public function submissions()
    {
        return $this->hasMany('Submission');
    }
}

class Submission extends \Eloquent {
    public function user()
    {
        return $this->form->category->user();
    }
    public function category()
    {
        return $this->form->category();
    }
    public function form()
    {
        return $this->belongsTo('App\Models\Form');
    }
}

Answer 1

对于链接关系，这并不是真正有效的...

你能做的，是这样的：

$submissions = Submission::whereHas('form.category.user', function($q){
    $q->where('id', 1);
})->get();

请注意 具有嵌套关系的 whereHas 仅在最新的 Laravel 4 版本中添加。确保 composer update.

Answer 2

如果我没听错你的问题，你需要正确定义关系。

根据laravel 4.2，您可以使用以下代码来定义关系：

class User extends \Eloquent implements ConfideUserInterface, BillableInterface{
    //...

    public function submissions(){
        return $this->hasMany('Submission');
    }
}

//...

class Submission extends \Eloquent {
    public function user()
    {
        return $this->belongsTo('User');
    }
    //...
}

要进一步阅读，请查看：http://laravel.com/docs/4.2/eloquent#relationships

通过 N 个模型的 hasMany 或 hasManyThrough 链

Chain of hasMany or hasManyThrough through N models

php

orm

laravel

eloquent

laravel-4