使用中间件为http响应头添加Access-Control-Allow-Origin

1.创建Cors中间件：

$ php artisan make:middleware Cors

2.编辑中间件：

<?php

namespace App\Http\Middleware;

use Closure;

class Cors
{
    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @return mixed
     */
    public function handle($request, Closure $next)
    {
        return $next($request)
            ->header('Access-Control-Allow-Origin', '*')

    }
}

3.将中间件添加到Kernel.php中：

protected $routeMiddleware = [
        'auth'          => \Illuminate\Auth\Middleware\Authenticate::class,
        'auth.basic'    => \Illuminate\Auth\Middleware\AuthenticateWithBasicAuth::class,
        'bindings'      => \Illuminate\Routing\Middleware\SubstituteBindings::class,
        'cache.headers' => \Illuminate\Http\Middleware\SetCacheHeaders::class,
        'can'           => \Illuminate\Auth\Middleware\Authorize::class,
        'guest'         => \App\Http\Middleware\RedirectIfAuthenticated::class,
        'signed'        => \Illuminate\Routing\Middleware\ValidateSignature::class,
        'throttle'      => \Illuminate\Routing\Middleware\ThrottleRequests::class,
        'cors'          => \App\Http\Middleware\Cors::class, // added
    ];

4.设置中间件对应的路由：

Route::middleware(['cors'])->group(function () {
    Route::post('/hogehoge', 'Controller@hogehoge');
});