[PHP框架从零到一] - 自动加载类

<?php

/**
* 自动加载类 
*/
class Loader
{
	// 自动加载搜索目录
	private static $loadPaths = [];

	// 添加自动加载路径
	public static function addAutoLoadPath($path)
	{
		self::$loadPaths[] = $path;
	}

	// 注册自动加载函数
	public static function register()
	{
		spl_autoload_register('self::autoload');
	}

	// 自动加载函数
	public static function autoload($className)
	{
		$className = str_replace(['\\', '_'], DIRECTORY_SEPARATOR, $className);
		foreach (self::$loadPaths as $loadPath) {
			$loadPath = rtrim($loadPath, DIRECTORY_SEPARATOR);
			$path = $loadPath . DIRECTORY_SEPARATOR . $className . '.php';
			if (self::import($path)) {
				break;
			}
		}
	}

	// 包含一个已存在的文件
	public static function import($path)
	{
		return file_exists($path) ? include_once($path) : false;
	}

}