Laravel 左连接错误：未定义属性：Illuminate\Database\Eloquent\Collection::$id

Question

我在 laravel 上使用 leftJoin，但出现错误

Undefined property: Illuminate\Database\Eloquent\Collection::$id

这里是控制器上的示例代码

$news = News::find($id)
            ->leftJoin('categories', 'news.category_id', '=', 'categories.id')
            ->get();

    //dd($news);

    return view('news.update')
    ->with('news', $news);

我一直在尝试使用 get()->first() 但它只显示第一条记录。如果我像这样在 blade 上使用 foreach，错误是一样的

<form class="form-horizontal" action="/news/{{$news->id}}" method="post" enctype="mulipart/form-data">
<select name="category_id">
    <option> - </option>
    @foreach($news as $news)
    <option value="{{ $news->category_id }}" selected>{{ $news->category }}</option>
    @endforeach 
</select> </form>

Answer 1

尝试这样做

$news = DB::table('news')
          ->leftJoin('categories', 'categories.id', '=', 'news.category_id')
          ->select('news.*', 'categories.*')
          ->get();

->select('news.', 'categories.') // 到select 来自新闻和类别的所有记录

<form class="form-horizontal" action="/news/{{$news[0]->id}}" method="post" enctype="mulipart/form-data">
  <select name="category_id">
      <option> - </option>
      @foreach($news as $news_data)
        <option value="{{ $news_data->category_id }}" selected>{{ $news_data->category }}</option>
      @endforeach 
  </select> 
</form>

Laravel 左连接错误：未定义属性：Illuminate\Database\Eloquent\Collection::$id

Laravel Error leftJoin : Undefined property: Illuminate\Database\Eloquent\Collection::$id

php

laravel

laravel-5.3

Laravel 左连接错误：未定义 属性：Illuminate\Database\Eloquent\Collection::$id

Laravel Error leftJoin : Undefined property: Illuminate\Database\Eloquent\Collection::$id

php

laravel

laravel-5.3

Laravel 左连接错误：未定义属性：Illuminate\Database\Eloquent\Collection::$id