Question

我有一个简单的查询，用主要类别和子类别填充菜单。这项工作完美无缺

  // in controller
$cat=Categories::all(); 
View::share('categories_menu',$cat); 

 // in view
 @foreach($categories_menu as $category_menu)
    @if($category_menu->has('subcategories'))
         <ul class="nav nav-stacked cat-nav">
              <li>
                  <a href="#">{{ $category_menu['category_name'] }} </a>
                        @if($category_menu->subcategories->count())
                          <ul>
                            @foreach($category_menu->subcategories as $subcategory)
                              <li class=""><a href="#">{{$subcategory->sub_cat_name}}</a></li>
                            @endforeach
                          </ul>
                        @endif
               </li>
            @else
               <li><a href="#"><i class="fa fa-link"></i> <span>{{ $category_menu->category_name }}</span></a></li>
            @endif
        </ul>
@endforeach

这样输出就像

Main Category
   -Sub Cat
   -Sub Cat
Second main category
   -Sub in second main category
   ...

问题是它还加载了空的子类别。我不想显示它们，我尝试通过加入所有三个表来更改查询 - category，sub_categories，products

这是到目前为止的查询

$cat = Categories::select('*', DB::raw('category.category_id AS category_id'))
    ->leftJoin('products', function($join) {
             $join->on('products.category_id', '=', 'category.category_id'); 
           })
    ->leftJoin('sub_category', function($secondjoin){
            $secondjoin->on('sub_category.category_id', '=', 'category.category_id');
           })
    ->whereNotNull('products.sub_cat_id')
    ->get();

结果很奇怪（图片）

它应该只显示两个主要类别，每个类别有一个子类别。在图像上，您可以看到我的产品表

Category 1
  -sub1
Category 2
  -sub3

如果需要更多来源或我能提供的东西。

使用模型更新：

分类模型

class Categories extends Eloquent {
    protected $table = 'category';
    protected $primaryKey = 'category_id';

    public $timestamps = false;

    public function products()
    {
        return $this->hasMany('Product', 'category_id');

    } 
    public function subcategories()
    {
        return $this->hasMany('SubCategories', 'category_id');
    } 
}

子类别模型

class SubCategories extends Eloquent {
    protected $table = 'sub_category';
    protected $primaryKey = 'sub_cat_id';

    public $timestamps = false;

    public function category()
    {
        return $this->belongsTo('Category', 'category_id');
    }

    public function products()
    {
       return $this->hasMany('Product', 'sub_cat_id');
    } 
}

产品型号

class Product extends Eloquent {
    protected $table = 'products';
    protected $primaryKey = 'product_id';

    public function categories()
    {
        return $this->hasMany('Categories', 'category_id');
    }

    public $timestamps = false;
}

Answer 1

 @foreach($categories_menu as $category_menu)
    @if($category_menu->has('subcategories'))
         <ul class="nav nav-stacked cat-nav">
              <li>
                  <a href="#">{{ $category_menu['category_name'] }} </a>
                        @if($category_menu->subcategories->count())
                          <ul>
                            @foreach($category_menu->subcategories as $subcategory)
                              @if($subcategory->products->count())
                                 <li class=""><a href="#">{{$subcategory->sub_cat_name}}</a></li>
                              @endif
                            @endforeach
                          </ul>
                        @endif
               </li>
            @else
               <li><a href="#"><i class="fa fa-link"></i> <span>{{ $category_menu->category_name }}</span></a></li>
            @endif
        </ul>
@endforeach

我添加了子系统的条件，只有当他们的产品数量大于0时才会显示。

仅在包含Laravel的产品时才显示菜单上的子类别

1 个答案: