"Property does not exist on this collection instance" 加入时出错 laravel 5.4

Question

UserAcademyController.php

    public function view_video()
{
    $materialList = DB::table('material')
        ->join('material_group', 'material.group_id', '=', 'material_group.id')
        ->select('material.*', 'material_group.group_thumbnail_url')
        ->get();

    return view('user-academy.view_video', ['materialList' => $materialList]);
}

view_video.blade.php

 @foreach ($materialList as $material)
        <div class="col-sm-6 col-lg-4 col-md-4">
            <div class="thumbnail">
                <a href="{!! url('user-academy/view/' . $material->id)!!}">
                    @if($material->thumbnail_url !== null)
                        <img src="{{$material->thumbnail_url}}"
                             style="width: 700px; height: 300px">
                    @elseif($materialList->group_thumbnail_url !== null)
                        <img src="{{$materialList->group_thumbnail_url}}"
                             style="width: 700px; height: 300px">
                    @elseif($material->thumbnail_url !== null && $materialList->group_thumbnail_url !== null)
                        <img src="http://www.independentmediators.co.uk/wp-content/uploads/2016/02/placeholder-image.jpg"
                             style="width: 700px; height: 300px">
                    @endif
                </a>
                <div class="caption">
                    <h4 class="pull-right text-success">${{$material->price}} </h4>

                    <h4>
                        <a href="{!! url('user-academy/view/' . $material->id)   !!}">{{ $material->title }}</a>
                    </h4>
                    <hr>
                    <p class="description">{!!  $material->description  !!}  </p>
                </div>
            </div>
        </div>
    @endforeach

This is the "material" table

This is the "material_group" table

即使我完全复制了 laravel 文档中的所有内容并观看了很多关于这个主题的视频，我还是收到了这个错误我是一个新的程序员，所以这可能是一个非常明显的错误，但我已经花了相当多的时间时间看代码，就是找不到错误所在！

Answer 1

您正在尝试访问 Collection class 上的 group_thumbnail_url 属性，这肯定不存在，这就是您收到该错误的原因。

解决办法是把$materialList->group_thumbnail_url换成material->group_thumbnail_url

"Property does not exist on this collection instance" 加入时出错 laravel 5.4

"Property does not exist on this collection instance" error while joining in laravel 5.4

laravel

laravel-5.4