访问控制-白红宇

访问控制

阅读量：4878 次

发布时间：2019-06-11

本文共 1758 字，大约阅读时间需要 5 分钟。

探究public , private , protected三种类型的数据的访问控制

其中public能被自身，子类，外部访问；

protected 能被自身和子类访问，不能被外部直接访问；

private 只能被自身访问，不能被子类和外部访问。

1 
     name." is eating ".$food."
";11     }12 13     public function info() {14         //通过自身调用private数据传到外部15         echo "HUMAN:".$this->name.";".$this->height.";".$this->isHungry ."
";16     }17 }18 19 20 class NbaPlayer extends Human{21     22     public $team="Bull";23     public $playerNumber="23";24 25     private $age = "40";//private的类成员只能在内部被访问26 27     function __construct($name,$height,$weight,$team,$playerNumber) {28         echo "In NbaPlayer constructor"."
";29         $this->name = $name; 30         $this->height = $height;31         $this->weight = $weight;32         $this->team = $team;33         $this->playerNumber = $playerNumber;34       //  echo $this->isHungry."
";  调用出错35     }36 37     function __destruct() {38         echo "Destroying".$this->name."
";39     }40 41     //方法定义42     public function run() {43         echo "Running"."
";44     }45 46     public function jump() {47         echo "Jumping"."
";48     }49     public function dribble() {50         echo "Dribbling"."
";51     }52     public function shoot() {53         echo "shooting"."
";54     }55     public function dunk() {56         echo "Dunking"."
";57     }58     public function pass() {59         echo "passing"."
";60     }61 62     public function getAge() {  //通过子类调用protected的数据，传到外部访问63         //外部不能直接访问，所以可以在内部对数据进行改动，使外部不能得到真实数据64         echo $this->name."'s age is ".($this->age-2) ."
";  65     }66 }67 68 $jordan = new NbaPlayer("Jordan","198cm","98kg","Bull","23");69  $jordan->getAge() ."
";70  //$jordan->height;  直接访问height会出错71 72  $jordan->info();