为 foreach() Facade\Ignition\Exceptions\

Question

@foreach没有语句，代码运行良好。添加后，我收到以下错误：

Undefined variable: articles (View: C:\laravel\laravel\resources\views\about.blade.php)

$articles is undefined.

Make the variable optional in the blade template. Replace {{ $articles }} with {{ $articles ?? '' }}

当我添加?? ''它时，它会产生错误：

Facade\Ignition\Exceptions\ViewException

Invalid argument supplied for foreach()

这是更大胆的完整代码： https ://github.com/matthoek/Articles

这是我的看法：

        <? if (is_array($articles) || is_object($articles)) ?>

            {

                @foreach ($articles ?? '' as $article)

                {

                    <li class = "first">

                        <h3>{{ $article->title}}</h3>

                        <p><a href="#">{{ $article->excerpt }}</a></p>          

                    </li>

                @endforeach

                }           

            }

        </ul>

这是我的控制器

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;

use App\Http\Requests;

use App\Http\Controllers\Controller;

use App\Article;

class ArticlesController extends Controller

{

    public function index()

    {

        $articles = App/Article::latest()->get();

        //$articles = Review::all();

        //$article = Review::all();

        return view('articles.index',['articles'=>$articles]);

        //return view('articles.index', ['articles' => $articles]);

    }

    public function show($id)

    {

        $article = App/Article::find($id);

        //return view('articles.show', ['article' => $article]);

        return view('articles.show')->with('article');

    }

    public function create()

    {

        return view('articles.create');

    }

将路由文件的部分更改为以下内容，但似乎不起作用。

 return view('about')->with(['article'=> $article]);

我已确保以下内容在我app/Http/Kernel.php的middlewareGroups财产中web \Illuminate\View\Middleware\ShareErrorsFromSession::class,

我已将 foreach 循环更改为 each 循环，并且在线上出现相同的错误：

<h3>{{article->title}}</h3>

让我知道我是否应该发布更多代码。

Answer 1

在您的路线中：&nbsp; &nbsp; Route::get('/about', function () {&nbsp; &nbsp; &nbsp; &nbsp; $articles = App\Article::latest()->get();&nbsp; &nbsp; &nbsp; &nbsp; return view('about', compact('about', 'articles'));&nbsp; &nbsp; });它将返回一个集合，您可以循环它：&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<ul>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; @foreach ($articles as $article)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <li class = "first">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<h3>{{ $article->title}}</h3>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;<p><a href="#">{{ $article->excerpt }}</a></p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </li>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; @endforeach&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </ul>

Answer 2

更新你的观点&nbsp;<? if (is_array($articles) || is_object($articles)) ?>&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; @foreach($articles as $article)&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <li class = "first">&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <h3>{{ $article->title}}</h3>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <p><a href="#">{{ $article->excerpt }}</a></p>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </li>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; @endforeach&nbsp; &nbsp;&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; </ul>错误在你的 foreach 循环中：https ://www.php.net/manual/en/control-structures.foreach.php