php中如何在外部修改类的私有或受保护属性值

php中怎么在外部修改类的私有或受保护属性值

在做单元测试框架时，发现了个比较郁闷的问题：测试人员需要在类外修改类的private或protected成员变量的值，而这些变量没有抽象成public的属性，同时为了代码量的问题，也不可能修改要测试的类。怎么在类外修改类的私有变量呢？请看下面的关键代码：

类文件sellAction.php， 内容如下：

<?phpclass SellAction{	protected $cUid;	private $id;	public $pId;	public function output(){		echo "output protected cUid :".$this->cUid;		echo "<br>";		echo "output private id :".$this->id;		echo "<br>";		echo "output public pId:".$this->pId;		echo "<br>";	}}

测试文件test.php，内容如下：

<?phprequire "sellAction.php";function initReferenceAttr(& $reference, $arr){	        if(!is_object($reference))        {            throw new Exception('reference must be object');        }        if(!is_array($arr))        {            throw new Exception('arr must be array');        }		$cls = get_class($reference);	$reflectCls = new ReflectionClass ($cls);        foreach($arr as $key => $val)        {            	$pro = $reflectCls->getProperty($key);		if($pro && ($pro->isPrivate() || $pro->isProtected())){			$pro->setAccessible(true);			$pro->setValue($reference, $val);		}else{			$reference->$key = $val;		}        }        return true;}$act = new SellAction();echo "not set private protect public var";echo "<br>";var_dump($act);$act->output();$attr = array('cUid'=>'234556', 'pId'=>'987676757', 'id'=> '782100');initReferenceAttr($act, $attr);echo "<br>";print_r($attr);echo "<br>";echo "<br>";echo "set private protect public var ";echo "<br>";var_dump($act);echo "<br>";$act->output();

在浏览器中，直接浏览test.php，内容大致如下：

not set private protect public varobject(SellAction)#1 (3) { ["cUid":protected]=> NULL ["id":"SellAction":private]=> NULL ["pId"]=> NULL } output protected cUid :output private id :output public pId:Array ( [cUid] => 234556 [pId] => 987676757 [id] => 782100 ) set private protect public var object(SellAction)#1 (3) { ["cUid":protected]=> string(6) "234556" ["id":"SellAction":private]=> string(6) "782100" ["pId"]=> string(9) "987676757" } output protected cUid :234556output private id :782100output public pId:987676757

上面的demo主要是通过反射实现该功能。反射功能需要php版本>=5.3，反射的相关信息请参阅：http://php.net/manual/en/book.reflection.php