思维导图自取
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实现

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通过原型链来实现继承

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例子

  1. <script>
  2.          // 父类，人类
  3.          function People(name, age, sex) {
  4.             this.name = name;
  5.             this.age = age;
  6.             this.sex = sex;
  7.         }
  8.         People.prototype.sayHello = function () {
  9.             console.log('你好，我是' + this.name + '我今年' + this.age + '岁了');
  10.         };
  11.         People.prototype.sleep = function () {
  12.             console.log(this.name + '开始睡觉，zzzzz');
  13.         };
  15.         // 子类，学生类
  16.         function Student(name, age, sex, scholl, studentNumber) {
  17.             this.name = name;
  18.             this.age = age;
  19.             this.sex = sex;
  20.             this.scholl = scholl;
  21.             this.studentNumber = studentNumber;
  22.         };
  23.         // 关键语句，实现继承
  24.         Student.prototype = new People();
  26.         Student.prototype.study = function () {
  27.             console.log(this.name + '正在学习');
  28.         };
  29.         Student.prototype.exam = function () {
  30.             console.log(this.name + '正在考试，加油！');
  31.         };
  33.         // 实例化
  34.         var hanmeimei = new Student('韩梅梅', 9, '女', '慕课小学', 100556);
  36.         hanmeimei.study();
  37.         hanmeimei.sayHello();
  38.         hanmeimei.sleep();
  39. </script>

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并且子类是可以重写父类的方法的

  1. // 重写、复写（override）父类的sayHello
  2.         Student.prototype.sayHello = function () {
  3.             console.log('敬礼！我是' + this.name + '我今年' + this.age + '岁了');
  4.         }