如何修复未定义的变量:Laravel 中 domPDF 中的协作者

how to fix Undefined variable: collaborators in domPDF in Laravel

我将使用 domPDF 打印 PDF。这是我的 CollaboPDFController.php:

<?php

namespace App\Http\Controllers;

use Illuminate\Http\Request;

use App\Http\Requests;
use App\Http\Controllers\Controller;
use PDF;
use App\Collaboration;

class CollaboPDFController extends Controller
{
    public function getPDF(){
        $collaborators = Collaboration::all();
        $pdf = PDF::loadView('collaborators.form',['Collaborators'=>$collaborators]);
        return $pdf->stream('form.collaborators');
    }
    //
}

这是我的 blade 视图 我将打印为 pdf 文件。它是协作者文件夹中的 form.blade.php 个文件。

<div class="col-md-4" style="border:1px solid #ccc;margin-left:15px;padding:10px;">
        <h4 class="page-header">
            Collaborators
        </h4>
        @if($collaborators)
           @foreach( $collaborators as $collaborator)
                <div>
                    <div>
                        <span>
                            <img src="{{ $collaborator->user()->first()->getAvatarUrl() }}" />
                             {{ $collaborator->user()->first()->username}}
                             {{ $collaborator->user()->first()->id}}

                        </span>
                    </div> 

据我所知,变量是区分大小写的,尝试替换 ['Collaborators'=>$collaborators]['collaborators'=>$collaborators]