将HandleCors类添加到config/app.php别名部分，如下所示。

'cors' => \Fruitcake\Cors\HandleCors::class,

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在将HandleCors添加到config/app.php后，是否运行了composer dump-autoload命令？

我删除了路由器上的中间件

Route::group(['middleware' => 'cors'], function() {
    Route::middleware('auth:api')->namespace('Api')->group(function () {

 
        Route::middleware('admin')->prefix('admin')->namespace('Admin')->group(function() {
            Route::get('dashboard/statistics', 'DashboardController@index');

...

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只是

Route::middleware('admin')->prefix('admin')->namespace('Admin')->group(function() {
    Route::get('dashboard/statistics', 'DashboardController@index');

型

这可能发生在升级laravel应用程序之后。
您必须将App\Http\Kernel.php的中间件数组中的**\Fruitcake\Cors\HandleCors：：class**替换为

\Illuminate\Http\Middleware\HandleCors::class,

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现在将是：

protected $middleware = [
        // \App\Http\Middleware\TrustHosts::class,
        \App\Http\Middleware\TrustProxies::class,
        \Illuminate\Http\Middleware\HandleCors::class,
        \App\Http\Middleware\PreventRequestsDuringMaintenance::class,
        \Illuminate\Foundation\Http\Middleware\ValidatePostSize::class,
        \App\Http\Middleware\TrimStrings::class,
        \Illuminate\Foundation\Http\Middleware\ConvertEmptyStringsToNull::class,
    ];

型