从空值 Laravel 8 创建默认对象
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【中文标题】从空值 Laravel 8 创建默认对象【英文标题】：Creating default object from empty value Laravel 8 【发布时间】：2021-05-22 03:09:19 【问题描述】：我正在学习 YouTube Laravel 8 电子商务教程，但在尝试从管理面板更新商店产品时遇到了错误 Creating default object from empty value。我已经尝试了在这里和谷歌上可以找到的所有答案（检查任何拼写错误的单词，需要组件和 web.php 文件中的每个必要组件等）。我完全按照教程中的内容做了，到目前为止一切正常。
这是我的看法：
<div class="panel-body">
@if(Session::has('message'))
<div class="alert alert-success" role="alert"> Session::get('message') </div>
@endif
<form action="" class="form-horizontal" enctype="multipart/form-data"
wire:submit.prevent="updateProduct">
<div class="form-group">
<label for="" class="col-md-4 control-label">Product Name</label>
<div class="col-md-4">
<input type="text" placeholder="Product Name" class="form-control input-md" wire:model="name" wire:keyup="generateSlug"/>
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label">Product Slug</label>
<div class="col-md-4">
<input type="text" placeholder="Product Slug" class="form-control input-md" wire:model="slug"/>
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label">Short Description</label>
<div class="col-md-4">
<textarea class="form-control input-md" placeholder="Short Description"
wire:model="short_description"></textarea>
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label">Description</label>
<div class="col-md-4">
<textarea class="form-control input-md" placeholder="Description" wire:model="description">
</textarea>
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label">Regular Price</label>
<div class="col-md-4">
<input type="text" placeholder="Regular Price" class="form-control input-md"
wire:model="regular_price"/>
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label">Sale Price</label>
<div class="col-md-4">
<input type="text" placeholder="Sale Price" class="form-control input-md"
wire:model="sale_price"/>
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label">SKU</label>
<div class="col-md-4">
<input type="text" placeholder="SKU" class="form-control input-md" wire:model="SKU" />
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label">Stock</label>
<div class="col-md-4">
<select name="" id="" class="form-control" wire:model="stock_status">
<option value="In Stock">In Stock</option>
<option value="Out of Stock">Out of Stock</option>
</select>
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label">Featured</label>
<div class="col-md-4">
<select name="" id="" class="form-control" wire:model="featured">
<option value="0">No</option>
<option value="1">Yes</option>
</select>
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label">Quantity</label>
<div class="col-md-4">
<input type="text" placeholder="Quantity" class="form-control input-md" wire:model="quantity"/>
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label">Product Image</label>
<div class="col-md-4">
<input type="file" class="input-file" wire:model="newimage"/>
@if ($newimage)
<img src=" $newimage->temporaryUrl() " />
@else
<img src=" asset('assets/images/products') /$image" />
@endif
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label">Category</label>
<div class="col-md-4">
<select name="" id="" class="form-control" wire:model="category_id">
<option value="">Select Category</option>
@foreach ($categories as $category)
<option value="$category->id">$category->name</option>
@endforeach
</select>
</div>
</div>
<div class="form-group">
<label for="" class="col-md-4 control-label"></label>
<div class="col-md-4">
<button type="submit" class="btn btn-primary">Update</button>
</div>
</div>
</form>
</div>
这是我的 Livewire 组件文件：
<?php
namespace App\Http\Livewire\Admin;
use App\Models\Product;
use App\Models\Category;
use Livewire\Component;
use Illuminate\Support\Str;
use Carbon\Carbon;
use Livewire\WithFileUploads;
class AdminEditProductComponent extends Component
use WithFileUploads;
public $name;
public $slug;
public $short_description;
public $description;
public $regular_price;
public $sale_price;
public $SKU;
public $stock_status;
public $featured;
public $quantity;
public $image;
public $category_id;
public $newimage;
public $product_id;
public function mount($product_slug)
$product = Product::where('slug', $product_slug)->first();
$this->name = $product->name;
$this->slug = $product->slug;
$this->short_description = $product->short_description;
$this->description = $product->description;
$this->regular_price = $product->regular_price;
$this->sale_price = $product->sale_price;
$this->SKU = $product->SKU;
$this->stock_status = $product->stock_status;
$this->featured = $product->featured;
$this->quantity = $product->quantity;
$this->image = $product->image;
$this->category_id = $product->category_id;
$this->newimage = $product->newimage;
$this->product_id = $product->product_id;
public function generateSlug()
$this->slug = Str::slug($this->name, '-');
**public function updateProduct()
$product = Product::find($this->product_id);
$product->name = $this->name;
$product->slug = $this->slug;
$product->short_description = $this->short_description;
$product->description = $this->description;
$product->regular_price = $this->regular_price;
$product->sale_price = $this->sale_price;
$product->SKU = $this->SKU;
$product->stock_status = $this->stock_status;
$product->featured = $this->featured;
$product->quantity = $this->quantity;
if ($this->newimage)
$imageName = Carbon::now()->timestamp. '.' . $this->newimage->extension();
$this->newimage->storeAs('products', $imageName);
$product->image = $imageName;
$product->category_id = $this->category_id;
$product->save();
session()->flash('message', 'Product has been updated successfully!');
**
public function render()
$categories = Category::all();
return view('livewire.admin.admin-edit-product-component',
['categories'=>$categories])->layout('layouts.base');
这是我的 web.php 文件
<?php
use App\Http\Livewire\Admin\AdminAddCategoryComponent;
use App\Http\Livewire\Admin\AdminAddProductComponent;
use App\Http\Livewire\Admin\AdminCategoryComponent;
use App\Http\Livewire\Admin\AdminDashboardComponent;
use App\Http\Livewire\Admin\AdminEditCategoryComponent;
use App\Http\Livewire\Admin\AdminProductComponent;
use App\Http\Livewire\Admin\AdminEditProductComponent;
use App\Http\Livewire\CartComponent;
use App\Http\Livewire\CategoryComponent;
use App\Http\Livewire\CheckoutComponent;
use App\Http\Livewire\DetailsComponent;
use App\Http\Livewire\HomeComponent;
use App\Http\Livewire\SearchComponent;
use App\Http\Livewire\ShopComponent;
use App\Http\Livewire\User\UserDashboardComponent;
use Illuminate\Support\Facades\Route;
/*
|--------------------------------------------------------------------------
| Web Routes
|--------------------------------------------------------------------------
|
| Here is where you can register web routes for your application. These
| routes are loaded by the RouteServiceProvider within a group which
| contains the "web" middleware group. Now create something great!
|
*/
//Route::get('/', function ()
// return view('welcome');
//);
Route::get('/', HomeComponent::class);
Route::get('/shop', ShopComponent::class);
Route::get('/cart', CartComponent::class)->name('product.cart');
Route::get('/checkout', CheckoutComponent::class);
Route::get('/product/slug', DetailsComponent::class)->name('product.details');
Route::get('/product-category/category_slug', CategoryComponent::class)->name('product.category');
Route::get('/search', SearchComponent::class)->name('product.search');
Route::middleware(['auth:sanctum', 'verified'])->get('/dashboard', function ()
return view('dashboard');
)->name('dashboard');
//For User or Customer
Route::middleware(['auth:sanctum', 'verified'])->group(function()
Route::get('/user/dashboard', UserDashboardComponent::class)->name('user.dashboard');
);
//For Admin
Route::middleware(['auth:sanctum', 'verified', 'authadmin'])->group(function()
Route::get('/admin/dashboard', AdminDashboardComponent::class)->name('admin.dashboard');
Route::get('/admin/categories', AdminCategoryComponent::class)->name('admin.categories');
Route::get('/admin/category/add', AdminAddCategoryComponent::class)->name('admin.addcategory');
Route::get('/admin/category/edit/category_slug', AdminEditCategoryComponent::class)->name('admin.editcategory');
Route::get('/admin/products', AdminProductComponent::class)->name('admin.products');
Route::get('/admin/product/add', AdminAddProductComponent::class)->name('admin.addproduct');
Route::get('/admin/product/edit/product_slug', AdminEditProductComponent::class)->name('admin.editproduct');
);
【问题讨论】：
【参考方案1】：你忘了添加这个
$this->product_id = $product->id;
挂载函数， 因此，当您尝试在 updateProduct 函数中从数据库接收数据时，它会收到一个空白值
【讨论】：
【参考方案2】：在 Here is my Livewire Component file:.
中使用 $this 代替 $product【讨论】：
正如目前所写，您的答案尚不清楚。请edit 添加其他详细信息，以帮助其他人了解这如何解决所提出的问题。你可以找到更多关于如何写好答案的信息in the help center。以上是关于从空值 Laravel 8 创建默认对象的主要内容，如果未能解决你的问题，请参考以下文章
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