使用反射动态加载第三方类用反射加载第三方类用处在于:
使用XML或其他配文件配置要加载的类,从而和系统源代码分离。
对加载的类进行类检查,是加载的类符合自己定义的结构。
<?phpabstract class Module {#核心Module类库function baseFunc() {echo "I am baseFunc";}abstract function execute();}class ModuleRunner {private $configData = array(#模拟xml配置,动态配置需要加载的Module"PersonModule" => array("person" => "bob"),"FtpModule" => array("host" => "example.com", "user" => "anon"));private $modules = array();function init() {#初始化ModuleRunner,加载配置中的Module$parent = new ReflectionClass("Module");foreach($this->configData as $moduleName => $params) {#检查配置中的Module是否合法$moduleClass = new ReflectionClass($moduleName);if(! $moduleClass->isSubclassOf($parent)) {#检查是否是Module的子类型throw new Exception("unknown type : {$moduleName}");}$module = $moduleClass->newInstance();foreach($moduleClass->getMethods() as $method) {#检查配置中的函数的参数格式是否正确$this->handleMothod($module, $method, $params);}array_push($this->modules, $module);#加载Module}}private function handleMothod(Module $module, ReflectionMethod $method, $params) {#检查Module中的方法参数是否和传入的$params名字相同,并且具有set方法
$name = $method->getName();$args = $method->getParameters();if(count($args) != 1 || substr($name, 0, 3) != "set") {#如果没有配置中的类的方法的参数个数不为1,或者方法名前3个字母不为set,返回falsereturn false;}$property = strtolower(substr($name, 3));if(!isset($params[$property])) {#如果方法名后三个字母与配置中的参数名不同,返回falsereturn false;}$argClass = $args[0]->getClass();#获取参数的类型if(empty($argClass)) {$method->invoke($module, $params[$property]);#参数无类型限制则直接调用set方法} else {$method->invoke($module, $argClass->newInstance($params[$property]));#有类型限制则新建一个实例并调用set方法}}public function getModules() {return $this->modules;}}class Person {#第三方类public $name;function __construct($name) {$this->name = $name;}}class FtpModule extends Module {#用户自定义第三方Moduleprivate $host = "default host";private $user = "default user";function setHost($host) {$this->host = $host;}function setUser($user) {$this->user = $user;}function execute() {echo "{$this->user} user {$this->host}";}}class PersonModule extends Module {#用户自定义第三方Moduleprivate $person;function setPerson(Person $person) {$this->person = $person;}function execute() {if(isset($person)) {echo "I am {$this->person->name}";} else {echo "I am no user";}}}$modRunner = new ModuleRunner();$modRunner->init();var_dump($modRunner);?>输出
object(ModuleRunner)#1 (2) { ["configData":"ModuleRunner":private]=> array(2) { ["PersonModule"]=> array(1) { ["person"]=> string(3) "bob" } ["FtpModule"]=> array(2) { ["host"]=> string(11) "example.com" ["user"]=> string(4) "anon" } } ["modules":"ModuleRunner":private]=> array(2) { [0]=> object(PersonModule)#4 (1) { ["person":"PersonModule":private]=> object(Person)#10 (1) { ["name"]=> string(3) "bob" } } [1]=> object(FtpModule)#3 (2) { ["host":"FtpModule":private]=> string(11) "example.com" ["user":"FtpModule":private]=> string(4) "anon" } } }通过反射获得类源码
<?phpfunction getSource(ReflectionClass $ref) {$path = $ref->getFileName();#获取脚本文件文件名$file = file($path); #file()方法获取文件内容,并将内容保存在一个数组中,数组每个元素保存一行内容$start = $ref->getStartLine();#获取类在脚本中的第一行行号$end = $ref->getEndLine();#获取类在脚本中最后一行的行号$source = implode(array_slice($file, $start - 1, $end - $start + 1));#拼装类源码var_dump($source);}class Person {public $age;private $name;function say() {echo "yes";}}$ref = new ReflectionClass("Person");getSource($ref);?>