Model.php第2794行出现错误异常：Laravel 5.2中的偏移量类型非法*

我在创建产品时遇到了一个问题，类似这样的错误消息会出现“ErrorException in Model.php第2794行：非法偏移类型”

Model Product.php

<?php

namespace App;

use Illuminate\Database\Eloquent\Model;

class Product extends Model
{
    protected $fillable = ['name','description','image','size','price','category_id'];
    protected $primaryKey = ['product_id'];

    public function category()
    {
        $this->belongsTo(Category::class);
    }
}

---

我想是因为默认名称更改了。做这个改变并尝试一下

public function category()
{
    $this->belongsTo(Category::class, 'category_id', 'category_id');
}

或者图像未设置或为空，请尝试将其添加为：

if ($request->hasFile('image')) {
   $data['image'] = $this->saveimage($request->file('image'));
}else{
   $data['image'] = '';
}

我明白了：

array:7 [▼
  "_token" => "dkbgGdfB1wP5rTRlGmKmo0rItrnV5T1pvnj65Uc3"
  "name" => "Bukan Hekel"
  "description" => "Bukan Hekel"
  "price" => "120000"
  "size" => "12"
  "category_lists" => array:1 [▼
    0 => "1"
  ]
  "image" => UploadedFile {#215 ▼
    -test: false
    -originalName: "bukanhekel.jpeg"
    -mimeType: "image/jpeg"
    -size: 54465
    -error: 0
    path: "/tmp"
    filename: "phpnjDRJA"
    basename: "phpnjDRJA"
    pathname: "/tmp/phpnjDRJA"
    extension: ""
    realPath: false
    writable: false
    readable: false
    executable: false
    file: false
    dir: false
    link: false
  }
]

在产品模型类中，更改此行
protected$primaryKey=['Product_id']到
受保护的$primaryKey='product_id'应该可以解决此错误。
所以，图像可能返回空值。我编辑我的答案并尝试一下，你也可以使用dd（$request->all（））进行检查。那么在具有复合主键的架构上使用Faker/Factories是否存在已知问题？Faker可以很好地为我生成所有内容，除了具有
$primaryKey=['key1'、'key2'、'key3']
<?php

/*
|--------------------------------------------------------------------------
| Application Routes
|--------------------------------------------------------------------------
|
| Here is where you can register all of the routes for an application.
| It's a breeze. Simply tell Laravel the URIs it should respond to
| and give it the controller to call when that URI is requested.
|
*/

// Front End
Route::get('/', 'CatalogsController@index')->name('index');

// Auth
Route::auth();
Route::get('/home', 'HomeController@index');

// Back End
Route::group(['prefix' => 'backend', 'middleware' => ['auth','admin']], function() {
    Route::get('/', function() {
        return view('admin.index');
    })->name('backend.index');

    Route::resource('categories', 'CategoryController');
    Route::resource('products', 'ProductController');
});

public function category()
{
    $this->belongsTo(Category::class, 'category_id', 'category_id');
}

if ($request->hasFile('image')) {
   $data['image'] = $this->saveimage($request->file('image'));
}else{
   $data['image'] = '';
}

array:7 [▼
  "_token" => "dkbgGdfB1wP5rTRlGmKmo0rItrnV5T1pvnj65Uc3"
  "name" => "Bukan Hekel"
  "description" => "Bukan Hekel"
  "price" => "120000"
  "size" => "12"
  "category_lists" => array:1 [▼
    0 => "1"
  ]
  "image" => UploadedFile {#215 ▼
    -test: false
    -originalName: "bukanhekel.jpeg"
    -mimeType: "image/jpeg"
    -size: 54465
    -error: 0
    path: "/tmp"
    filename: "phpnjDRJA"
    basename: "phpnjDRJA"
    pathname: "/tmp/phpnjDRJA"
    extension: ""
    realPath: false
    writable: false
    readable: false
    executable: false
    file: false
    dir: false
    link: false
  }
]