Question

我尝试与3个模型建立关系：

Cities.php //table cities
id
name

Neighbourhoods.php //table neighbourhoods
id
name
city_id

Blocks.php //table blocks
id
name
neighbourhood_id

我的模特看起来像这样： Cities.php

public function neighbourhoods()
{
    return $this->hasManyThrough('App\Neighbourhoods', 'App\Blocks', 'neighbourhood_id', 'city_id', 'id');
}

Neighbourhoods.php

public function blocks()
{
    return $this->hasMany('App\Blocks', 'neighbourhood_id', 'id');
}

Blocks.php

public function neighbourhoods()
{
    return $this->belongsToMany('App\Neighbourhoods', 'neighbourhood_id', 'id');
}

结果应该是：

results
 city1:
  neighbourhoods:
   neighbourhood1:
    block1
    block2
    block3
   neighbourhood2
    block1
    block2
 city2:
  neighbourhoods:
   neighbourhood1:
    blocks:
     block1
     block2
     block3
   neighbourhood2:
    blocks:
     block1
     block2

调用结果：

return Blocks::with('neighbourhoods')->get();

我知道我的模型没有正确命名。城市（奇异），邻居（singlar），Block（奇异）但传递参数shoud工作。我无法弄清楚它为什么不起作用。

基于@Gaurav Rai回应的关系解决方案

首先，我的模型命名错误。请使用复数形式命名数据库，例如：城市，邻域，块和模型，例如：City.php，Neighbourhood.php和Block.php

根据我的问题，解决方案是：

Cities.php

public function neighbourhoods()
{
    return $this->hasMany('App\Neighbourhoods', 'city_id', 'id');
     // because my model is called Cities.php,
     // the function will look by default 
     // for the column cities_id in neighbourhoods table, 
     // thats why we need to specifiy city_id column
}

public function blocks()
{
    return $this->hasManyThrough('App\Blocks', 'App\Neighbourhoods', 'city_id', 'neighbourhood_id', 'id');
}

Neighbourhoods.php

public function cities()
{
    return $this->belongsTo('App\Cities', 'city_id', 'id');
}

public function blocks()
{
    return $this->hasMany('App\Blocks', 'neighbourhood_id','id');
}

Blocks.php

public function neighbourhoods()
{
    return $this->belongsTo('App\Neighbourhoods', 'neighbourhood_id');
}

调用关系：

return Cities::with(['neighbourhoods', 'blocks'])->get();

Answer 1

我认为您的关系定义不明确：

Cities.php

public function neighbourhoods()
{
    return $this->hasMany('App\Neighbourhoods');
}
public function blocks()
{
    return $this->hasManyThrough('App\Neighbourhoods', 'App\Blocks');
}

Neighbourhoods.php

public function blocks()
{
    return $this->hasMany('App\Blocks');//by default it will consider id
}
public function city()
{
    return $this->belongsTo('App\City');
}

Blocks.php

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

流明/ laravel Eloquent hasManyThrough 3模型关系

1 个答案: