JavaScript原型链中的数据共享与方法共享实现

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>title</title>
  <script>
    function Student(name,age,sex) {
      this.name=name;
      this.age=age;
      this.sex=sex;
    }
    // 所有学生的身高都是188,所有人的体重都是55
    // 所有学生都要每天写500行代码
    // 所有学生每天都要吃一个10斤的西瓜
    //原型对象

    Student.prototype.height="188";
    Student.prototype.weight="55kg";
    Student.prototype.study=function () {
      console.log("学习,写500行代码,小菜一碟");
    };
    Student.prototype.eat=function () {
      console.log("吃一个10斤的西瓜");
    };
    //实例化对象,并初始化
    var stu=new Student("晨光",57,"女");
    console.dir(Student);
    console.dir(stu);

//    stu.eat();
//    stu.study();

  </script>
</head>
<body>


</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>title</title>
  <script>
    function Student(name, age, sex) {
      this.name = name;
      this.age = age;
      this.sex = sex;
    }
    //简单的原型写法
    Student.prototype = {
      //手动修改构造器的指向
      constructor:Student,
      height: "188",
      weight: "55kg",
      study: function () {
        console.log("学习好开心啊");
      },
      eat: function () {
        console.log("我要吃好吃的");
      }
    };

    var stu=new Student("鼎鼎大名",20,"男");
    stu.eat();
    stu.study();
    console.dir(Student);
    console.dir(stu);

  </script>
</head>
<body>


</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>title</title>
  <script>
    //原型中的方法,是可以相互访问的

    function Animal(name,age) {
      this.name=name;
      this.age=age;
    }
    //原型中添加方法
    // 吃完了就玩
    Animal.prototype.eat=function () {
      console.log("动物吃东西");
      this.play();
    };
    // 玩完了就睡
    Animal.prototype.play=function () {
      console.log("玩球");
      this.sleep();
    };
    Animal.prototype.sleep=function () {
      console.log("睡觉了");
    };

    var dog=new Animal("小苏",20);
    dog.eat();

    //原型对象中的方法,可以相互调用


  </script>
</head>
<body>


</body>
</html>