Laravel ErrorException，执行多个动态下拉答案

【问题标题】：Laravel ErrorException, Performing Multiple dynamic drop downLaravel ErrorException，执行多个动态下拉
【发布时间】：2018-04-20 11:43:04
【问题描述】：

我有四张桌子： asset_category 表（列'asset_category_id'，'category'），一个assets 表（列'asset_id'，'asset_category_id'，'manufacturer_id'，@987654328 @), manufacturers 表（列manufacturers_id、manufacturer）和departments 表（列department_id、department）。 asset 表列与其他三个表链接。我正在表单中执行动态下拉以插入到asset 表中

Asset.blade.php

<form action="{{url('/insertAsset')}}" method="POST" edata-parsley-validate novalidate>
    {{ csrf_field() }}
    <div class="form-group">
        <label for="userName">Asset ID*</label>
        <input type="text" name="asset_id" parsley-trigger="change" required placeholder="Asset ID" class="form-control" id="userName" disabled>
    </div>
    <div class="form-group">
        <label for="userName">Asset Category ID*</label>
        <select name="asset_category_id" parsley-trigger="change" required placeholder="Asset Category ID" class="form-control">
       <option>Select an Asset Category</option>
        @foreach( $asset_categories as $asset_category )
            <option value=" {{$asset_category->asset_category_id}}"> {{ $asset_category->category }} </option>
                @endforeach
        </select>
    </div>
    <div class="form-group">
        <label for="userName">Asset Manufacture ID*</label>
        <select name="manufacturer_id" parsley-trigger="change" required class="form-control">
            <option>Select a Manufacturer</option>
                @foreach( $manufacturers as $manufacturer )
                    <option value=" {{$manufacturer->manufacturer_id}}"> {{ $manufacturer->manufacturer }} </option>
                @endforeach
            </select>
    </div>
    <div class="form-group">
        <label for="userName">Department ID*</label>
        <select name="department_id" parsley-trigger="change" required placeholder="Department ID" class="form-control" >
            <option>Select a Department</option>
            @foreach( $departments as $department )
                <option value=" {{$department->department_id}}"> {{ $department->department }} </option>
            @endforeach
        </select>
    </div>

<div class="form-group text-right m-b-0">
<button class="btn btn-primary waves-effect waves-light" type="submit">
    Submit
</button>
</div>

资产控制器

<?php

namespace App\Http\Controllers;

use App\Asset;
use App\Asset_category;
use App\Manufacturer;
use App\Department; 

use Illuminate\Http\Request;

class AssetController extends Controller
{   
    public function asset_category(){
        $asset_categories = Asset_category::all();
    return view('asset', ['asset_categories' => $asset_categories]);
    }

    public function manufacturer(){
        $manufacturers = Manufacturer::all();
        return view('asset', ['manufacturers' => $manufacturers]);
    }

    public function department(){
        $departments = Department::all();
        return view('asset', ['departments' => $departments]);
    }    

}

Web.php

<?php    

Route::get('/asset', function (){
    return view('asset');
} );   

Route::get('/asset', 'AssetController@asset_category');
Route::get('/asset', 'AssetController@department');
Route::get('/asset', 'AssetController@manufacturer');    


/*POST */    
Route::post('/insertAsset', 'AssetController@add');

当运行应用程序时，我得到一个ErrorException，它指出：

Undefined variable: asset_categories (View: C:\xampp\htdocs\laravel_app\resources\views\asset.blade.php).

经过彻底的测试，我发现，只有一个下拉菜单显示，因为 laravel 仅从 web.php 的 3 个函数中的一个函数路由一个变量，而其他函数的另外两个变量没有发送到 @ 987654343@。所以现在我想要一种将其他变量路由到asset.blade.php 的方法。如果您理解它，请帮助。提前致谢。

【问题讨论】：

标签： php laravel laravel-5.4 laravel-routing laravel-blade

【解决方案1】：

首先，Laravel 只会匹配第一个具有特定 ID 和特定类型的路由。在这种情况下只会找到第一条路线GET /asset。

做我不明白你想做的事。您只需要创建一个方法，它将三个变量返回到视图

public function asset(){
    $asset_categories = Asset_category::all();
    $manufacturers = Manufacturer::all();
    $departments = Department::all();
    return view('asset', ['asset_categories' => $asset_categories, 
                     'manufacturers' => $manufacturers, 'departments' => $departments]);
}

而且只有一条路线 Route::get('/asset', 'AssetController@asset');

【讨论】：