如何使用Laravel 5.4

Question

時於laravel 5.4 視圖我有一個問題是這樣的錯誤包括functiont：

3/3) ErrorException Undefined variable: categories (View: C:\xampp\htdocs\blog\resources\views\partials\index.blade.php) (View: C:\xampp\htdocs\blog\resources\views\partials\index.blade.php)

我的索引：

@extends('layouts.master') 

@section('content') 

@include('partials.index') 


@endsection 
________ 
// this is index in partials 
<div class="container index-cat"> 
    <div class="row"> 
     <div class="col-md-12"> 

      <h1>Категория:</h1> 
      <div class="pull-right add-cat"> 
       <a href="{{url('categories/create')}}" class="btn btn-success">Дабавить Катигорию</a> 
      </div> 


      <div class="row"> 
       @foreach($categories as $cat) 
        <div class="col-sm-6 col-md-4"> 
         <div class="thumbnail"> 
          <img src="{{asset ('storage/' . $cat->photo)}}" alt="..."> 
          <div class="caption"> 
           <h3>{{$cat->title}}</h3> 
           <form action="{{url('categories/' . $cat->id)}}" method="POST"> 
            {{csrf_field()}} 
            {{method_field('DELETE')}} 
            <div class="buttons-bootstrap"> 
             <a href="{{url('categories/' . $cat->id . '/description')}}" class="btn btn-primary" role="button">подробности</a> 
             <a href="{{url('categories/' . $cat->id . '/edit')}}" class="btn btn-warning" role="button">редактировать</a> 
             <button type="submit" class="btn btn-danger">удалить</button> 

            </div> 

           </form> 


          </div> 
         </div> 
        </div> 
       @endforeach 
      </div> 

     </div> 

    </div> 
</div> 

我的控制器：

這是我的控制器

<?php 

    namespace App\Http\Controllers; 

    use Illuminate\Http\Request; 
    use Illuminate\Http\UploadedFile; 


    use App\Http\Requests\catRequest; 

    use App\Category; 
    use App\User; 
    use Auth; 
    use Illuminate\Support\Facades\Storage; 




    class CategoryController extends Controller 
    { 
     //middleware auth 
     public function __construct() 
     { 
      $this->middleware('auth'); 

     } 
     public function show($id) 
     { 

      $cat = Category::query()->find($id); 




      return view('categories.description' , ['categories' => $cat]); 
     } 

     public function index(){ 
      //$listCat = Category::all(); 

      $listCat = Category::where('user_id' , Auth::user()->id)->get(); 
      return view('categories.index' , ['categories' => $listCat]); 
     } 
     public function create(){ 
      return view('categories.create'); 
     } 
     public function store(catRequest $request ){ 


      //return $request->all(); 
      $cat = new Category(); 
      $cat->title = $request->input('title'); 
      $cat->description = $request->input('description'); 
      $cat->user_id = Auth::user()->id; 

      if($request->hasFile('photo')){ 
       $cat->photo = $request->photo->store('photo'); 
      } 
      $cat->save(); 
      session()->flash('success' , 'Катигория дабавлена'); 
      return redirect('categories'); 

     } 

     /** 
     * @param $id 
     * @return \Illuminate\Contracts\View\Factory|\Illuminate\View\View 
     */ 
     public function edit($id){ 

      $cat = Category::query()->find($id); 


      return view('categories.edit' , ['categories' => $cat]); 
     } 

     /** 
     * @param Request $request 
     * @param $id 
     */ 
     public function update(catRequest $request, $id){ 
      $cat = Category::query()->find($id); 
      $cat->title = $request->input('title'); 
      $cat->description = $request->input('description'); 
      if($request->hasFile('photo')){ 
       $cat->photo = $request->photo->store('photo'); 
      } 
      $cat->save(); 
      return redirect('categories'); 
     } 
     public function destroy(Request $request, $id){ 
      $cat = Category::query()->find($id); 
      $cat->delete(); 
      return redirect('categories'); 

     } 
    } 

Answer 1

看來，你的錯誤描述遺漏變量

ErrorException Undefined variable: categories.

這意味着刀片模板不能看到你正在使用的for循環$categories變量。

檢查您的web.php或app/Http/Controller/file.php其中正在調用刀片模板，並確保您將一個變量傳遞給視圖函數。

例如

return view('greeting', ['name' => 'James']); // <= passing a variable $name with string 'James' 

Laravel Reference https://laravel.com/docs/5.4/views