## 自动加载 每个文件既要申明命名空间又要手动 include 是非常不智能的事情，可以使用自动加载技术，让系统自己去加载文件。 ``` <?php class Loader { public function loadController($className) { $this->includeClass('controller', $className); } public function loadModel($className) { $this->includeClass('model', $className); } public function loadLibrary($className) { $this->includeClass('library', $className); } private function includeClass($classType, $className) { $fileName = APP_PATH . '/' . $classType . '/' . $className . '.php'; if(file_exists($fileName)) { include_once $fileName; } } } $loader = new Loader(); spl_autoload_register([$loader, 'loadController']); spl_autoload_register([$loader, 'loadModel']); spl_autoload_register([$loader, 'loadLibrary']); ?> ``` 参考链接：[spl_autoload_register](http://php.net/manual/zh/function.spl-autoload-register.php)