Laravel API 允许跨域请求

废话不多说，直接上代码

创建一个中间件 CrossMiddleware

<?php

namespace App\Http\Middleware;

use Closure;
use Response;

class CrossMiddleware
{
    /**
     * Handle an incoming request.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  \Closure  $next
     * @return mixed
     */
    public function handle($request, Closure $next)
    {

        $response = $next($request);
        $IlluminateResponse = 'Illuminate\Http\Response';
        $SymfonyResopnse = 'Symfony\Component\HttpFoundation\Response';
        $headers = [
            'Access-Control-Allow-Origin' => '*',//可以控制访问的域名
            'Access-Control-Allow-Methods' => 'POST, GET, OPTIONS, PUT, PATCH, DELETE',
            'Access-Control-Allow-Headers' => 'Origin, Content-Type, Cookie, X-CSRF-TOKEN, Accept, Authorization, X-XSRF-TOKEN',
            'Access-Control-Allow-Credentials'=>true
        ];

        if ($response instanceof $IlluminateResponse) {
            foreach ($headers as $key => $value) {
                $response->header($key, $value);
            }
            return $response;
        }

        if ($response instanceof $SymfonyResopnse) {
            foreach ($headers as $key => $value) {
                $response->headers->set($key, $value);
            }
            return $response;
        }

        return $response;

    }
}

因为想作用在api的路由中，所以可以在Kernel.php 中设置

    protected $middlewareGroups = [
        ....
        ....

        'api' => [
            // \Laravel\Sanctum\Http\Middleware\EnsureFrontendRequestsAreStateful::class,
            'throttle:api',
            \Illuminate\Routing\Middleware\SubstituteBindings::class,
            \App\Http\Middleware\CrossMiddleware::class
        ],
    ];

也可以放在 $middleware 中，这样就全局有效了！