目标类不存在。laravel 8 中的问题

Question

当使用 laravel 8 创建新项目时，出现此错误。Illuminate\Contracts\Container\BindingResolutionException 目标类 [SayhelloController] 不存在。http://127.0.0.1:8000/users/john<?php    use Illuminate\Support\Facades\Route;     Route::get('/', function () {    return view('welcome');});      Route::get('/users/{name?}' , [SayhelloController::class,'index']);在 Laravel 文档中，路由控制器类必须这样定义 // Using PHP callable syntax...Route::get('/users', [UserController::class, 'index']);// Using string syntax...Route::get('/users', 'App\Http\Controllers\UserController@index');目标类别<?phpnamespace App\Http\Controllers;use Illuminate\Http\Request;class SayhelloController extends Controller{    public function index($name = null)    {        return 'Hello '.$name;    }}所以我确实这么做了。

Answer 1

Laravel 8 更新了路由的编写方式

在 laravel 8 中你需要使用像

use App\Http\Controllers\SayhelloController;
Route::get('/users/{name?}' , [SayhelloController::class,'index']);

或者

Route::get('/users', 'App\Http\Controllers\UserController@index');

如果你想使用旧的方式

然后在RouteServiceProvider.php

添加这一行

 /**

     * This namespace is applied to your controller routes.

     *

     * In addition, it is set as the URL generator's root namespace.

     *

     * @var string

     */

    protected $namespace = 'App\Http\Controllers'; // need to add in Laravel 8

    

public function boot()

{

    $this->configureRateLimiting();

    $this->routes(function () {

        Route::prefix('api')

            ->middleware('api')

            ->namespace($this->namespace) // need to add in Laravel 8

            ->group(base_path('routes/api.php'));

        Route::middleware('web')

            ->namespace($this->namespace) // need to add in Laravel 8

            ->group(base_path('routes/web.php'));

    });

}

然后你可以使用像

Route::get('/users/{name?}' , [SayhelloController::class,'index']);

Route::resource('/users' , SayhelloController::class);

或者

Route::get('/users', 'UserController@index');