PHP函数

<?phpecho strncmp("I love China!","I love Shanghai!",6);?>

<?class User{private $name;public function  getName(){return "UserName is ".$this->name;}}class NormalUser extends User {private $age = 99;public function getAge(){return "age is ".$this->age;}}class UserAdmin{ //操作.public static function  getUserInfo(User $_user){if($_user instanceof NormalUser ){echo $_user->getAge();}else{echo "类型不对,不能使用这个方法.";}}}$User = new User(); // 这里new的是User.UserAdmin::getUserInfo($User);?>