Laravel - 子类别显示在主要类别下

Question

你好
我有一个关于类别和子类别的问题
我有这样的表:

ID----- 姓名---- ParentID
1 ------ A ---------- 0
2 ------ B ---------- 0
3 ------ C ---------- 1
我已经显示 A B C ok 。但我需要它会像这样显示:
一个
-- C
B

只是有问题，找不到这样做的方法(在父类别下创建子类别)

注意:我在 Views 中使用 make query 成功了，但我认为它不太好。
我想找到更好的方法
非常感谢

Answer 1

显示子、子和子类别 -

型号

1. 迁移以下类别表:

   Schema::create('categories', function (Blueprint $table) {
       $table->increments('id');
       $table->string('name');
       $table->tinyInteger('parent_id')->default(0);
       $table->timestamps();
   });
   

2. 输入您的类别和子类别，如下表结构:

   +-------------+----------------------+----------+
   | id          | name                 |parent_id |
   +-------------+----------------------+----------+
   |           1 | ELECTRONICS          |      0   |
   |           2 | TELEVISIONS          |      1   |
   |           3 | TUBE                 |      2   |
   |           4 | LCD                  |      2   |
   |           5 | PLASMA               |      2   |
   |           6 | PORTABLE ELECTRONICS |      1   |
   |           7 | MP3 PLAYERS          |      6   |
   |           8 | FLASH                |      7   |
   |           9 | CD PLAYERS           |      6   |
   |          10 | 2 WAY RADIOS         |      6   |
   +-------------+----------------------+----------+
   

Controller

1. MySQL层次递归查询

   $categories = DB::table('categories as c1')
       ->leftJoin('categories as c2','c2.parent_id','=','c1.id')
       ->leftJoin('categories as c3','c3.parent_id','=','c2.id')
       ->leftJoin('categories as c4','c4.parent_id','=','c3.id')
       ->select('c1.id as c1_id','c1.name as c1_name','c2.id as c2_id','c2.name as c2_name','c3.id as c3_id','c3.name as c3_name','c4.id  as c4_id','c4.name as c4_name')
       ->where('c1.parent_id','=',0)
       ->get();
   

输出:

+-----------------+--------------------------+------------------+-----------------+
|c1_id| c1_name   | c2_id| c2_name           | c3_id| c3_name   | c4_id| c4_name  |
+-----------------+--------------------------+------------------+-----------------+
| 1 | ELECTRONICS | 2 | TELEVISIONS          | 3 | TUBE         | NULL  |
| 1 | ELECTRONICS | 2 | TELEVISIONS          | 4 | LCD          | NULL  |
| 1 | ELECTRONICS | 2 | TELEVISIONS          | 5 | PLASMA       | NULL  |
| 1 | ELECTRONICS | 6 | PORTABLE ELECTRONICS | 7 | MP3 PLAYERS  | 8   | FLASH |
| 1 | ELECTRONICS | 6 | PORTABLE ELECTRONICS | 9 | CD PLAYERS   | NULL  |
| 1 | ELECTRONICS | 6 | PORTABLE ELECTRONICS | 10| 2 WAY RADIOS | NULL  |
+-------------+--------------------------------------+--------------+-------+

1. 然后，将$categories 值放入数组。

   $all_categories = [];
   $category_c1_id = '';
   $category_c2_id = '';
   $category_c3_id = '';
   $category_c4_id = '';
   $c1_id = -1;
   $c2_id = -1;
   $c3_id = -1;
   $c4_id = -1;
   foreach ($categories as $k=>$category){
       if($category->c1_id != $category_c1_id){
           $c1_id = $c1_id +1;
           $all_categories[$c1_id]['id'] = $category->c1_id;
           $all_categories[$c1_id]['name'] = $category->c1_name;
           $c2_id = -1;
       }
       if($category->c2_id != $category_c2_id && $category->c2_id <> NULL){
           $c2_id = $c2_id +1;
           $all_categories[$c1_id]['children'][$c2_id]['id'] = $category->c2_id;
           $all_categories[$c1_id]['children'][$c2_id]['name'] = $category->c2_name;
           $c3_id = -1;
       }
       if($category->c3_id != $category_c3_id && $category->c3_id <> NULL){
           $c3_id = $c3_id +1;
           $all_categories[$c1_id]['children'][$c2_id]['children'][$c3_id]['id'] = $category->c3_id;
           $all_categories[$c1_id]['children'][$c2_id]['children'][$c3_id]['name'] = $category->c3_name;
           $c4_id = -1;
       }
       if($category->c4_id != $category_c4_id && $category->c3_id <> NULL){
           $c4_id = $c4_id +1;
           $all_categories[$c1_id]['children'][$c2_id]['children'][$c3_id]['children'][$c4_id]['id'] = $category->c4_id;
           $all_categories[$c1_id]['children'][$c2_id]['children'][$c3_id]['children'][$c4_id]['name'] = $category->c4_name;
       }
       $category_c1_id = $category->c1_id;
       $category_c2_id = $category->c2_id;
       $category_c3_id = $category->c3_id;
       $category_c4_id = $category->c4_id;
   }
   return $all_categories;
   

   输出:

   $categories = [
     ['id' => 1, 'name' => 'TV & Home Theather'],
     ['id' => 2, 'name' => 'Tablets & E-Readers'],
     ['id' => 3, 'name' => 'Computers', 'children' => [
       ['id' => 4, 'name' => 'Laptops', 'children' => [
         ['id' => 5, 'name' => 'PC Laptops'],
         ['id' => 6, 'name' => 'Macbooks (Air/Pro)']
       ]],
       ['id' => 7, 'name' => 'Desktops'],
       ['id' => 8, 'name' => 'Monitors']
     ]],
     ['id' => 9, 'name' => 'Cell Phones']
   ];
   

查看

1. 现在显示在选择产品上传选项。

   <div class="form-group">
       <label>Select Categories</label><br/>
       @foreach($categories as $category)
           @php($category = (object)$category)
           <div class="form-check">
               <label class="form-check-label" for="{{$category->id}}">
                   {{ Form::checkbox('category_ids[]', $category->id, null, array('id'=>$category->id)) }}
                   {{$category->name}}
               </label>
               @if(isset($category->children))
                   @foreach($category->children as $subcategory)
                       @php($subcategory = (object)$subcategory)
                       <div class="form-check" style="margin-left: 15px;">
                           <label class="form-check-label" for="{{$subcategory->id}}">
                               {{ Form::checkbox('category_ids[]', $subcategory->id, null, array('id'=>$subcategory->id)) }}
                               {{$subcategory->name}}
                           </label>
                           @if(isset($subcategory->children))
                               @foreach($subcategory->children as $subsubcategory)
                                   @php($subsubcategory = (object)$subsubcategory)
                                   <div class="form-check" style="margin-left: 15px;">
                                       <label class="form-check-label" for="{{$subsubcategory->id}}">
                                           {{ Form::checkbox('category_ids[]', $subsubcategory->id, null, array('id'=>$subsubcategory->id)) }}
                                           {{$subsubcategory->name}}
                                       </label>
                                   </div>
                               @endforeach
                           @endif
                       </div>
                   @endforeach
               @endif
           </div>
       @endforeach
   </div>
   

   开启菜单选项

   <ul class="nav primary clone-main-menu toggle-slide-menu" id="mercado_main" data-menuname="Main menu" >
     @foreach($categories as $category)
         <li class="menu-item menu-item-has-children item-megamenu" >
             <a href="#" title="Digital & Electronics" class="link-term mercado-item-title">{{$category['name']}}</a>
             <div class="wrap-megamenu">
                 <div class="megamenu-content min-height-510 bg-vertical-digital">
                     @if(isset($category['children']))
                         <div class="row">
                             @foreach($category['children'] as $subcategory)
                                 <div class="col-lg-3 col-md-3">
                                     <div class="wrap-vertical-nav">
                                         <h2 class="menu-title"><a href="#" class="link-term">{{$subcategory['name']}}</a></h2>
                                         @if(isset($subcategory['children']))
                                             <ul>
                                                 @foreach($subcategory['children'] as $subcategory)
                                                     <li class="menu-item"><a href="#" class="link-term">{{$subcategory['name']}}</a></li>
                                                 @endforeach
                                             </ul>
                                         @endif
   
                                     </div>
                                 </div>
                             @endforeach
                         </div>
                     @endif
                 </div>
             </div>
         </li>
     @endforeach
   </ul>