<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>title</title>
<script>
// function Person(name,age,sex,weight) {
// this.name=name;
// this.age=age;
// this.sex=sex;
// this.weight=weight;
// }
// Person.prototype.sayHi=function () {
// console.log("您好");
// };
// function Student(score) {
// this.score=score;
// }
// //希望人的类别中的数据可以共享给学生---继承
// Student.prototype=new Person("小明",10,"男","50kg");
//
// var stu1=new Student("100");
// console.log(stu1.name,stu1.age,stu1.sex,stu1.weight,stu1.score);
// stu1.sayHi();
//
// var stu2=new Student("120");
// stu2.name="张三";
// stu2.age=20;
// stu2.sex="女";
// console.log(stu2.name,stu2.age,stu2.sex,stu2.weight,stu2.score);
// stu2.sayHi();
// var stu3=new Student("130");
// console.log(stu3.name,stu3.age,stu3.sex,stu3.weight,stu3.score);
// stu3.sayHi();
//为了数据共享,改变原型指向,做到了继承---通过改变原型指向实现的继承
//缺陷:因为改变原型指向的同时实现继承,直接初始化了属性,继承过来的属性的值都是一样的了,所以,这就是问题
//只能重新调用对象的属性进行重新赋值,
//解决方案:继承的时候,不用改变原型的指向,直接调用父级的构造函数的方式来为属性赋值就可以了------借用构造函数:把要继承的父级的构造函数拿过来,使用一下就可以了
//借用构造函数:构造函数名字.call(当前对象,属性,属性,属性....);
//解决了属性继承,并且值不重复的问题
//缺陷:父级类别中的方法不能继承
function Person(name, age, sex, weight) {
this.name = name;
this.age = age;
this.sex = sex;
this.weight = weight;
}
Person.prototype.sayHi = function () {
console.log("您好");
};
function Student(name,age,sex,weight,score) {
//借用构造函数
Person.call(this,name,age,sex,weight);
this.score = score;
}
var stu1 = new Student("小明",10,"男","10kg",100);
console.log(stu1.name, stu1.age, stu1.sex, stu1.weight, stu1.score);
var stu2 = new Student("小红",20,"女","20kg","120");
console.log(stu2.name, stu2.age, stu2.sex, stu2.weight, stu2.score);
var stu3 = new Student("小丽",30,"妖","30kg","130");
console.log(stu3.name, stu3.age, stu3.sex, stu3.weight, stu3.score);
</script>
</head>
<body>
</body>
</html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>title</title>
<script>
// function Person(name,age,sex,weight) {
// this.name=name;
// this.age=age;
// this.sex=sex;
// this.weight=weight;
// }
// Person.prototype.sayHi=function () {
// console.log("您好");
// };
// function Student(score) {
// this.score=score;
// }
// //希望人的类别中的数据可以共享给学生---继承
// Student.prototype=new Person("小明",10,"男","50kg");
//
// var stu1=new Student("100");
// console.log(stu1.name,stu1.age,stu1.sex,stu1.weight,stu1.score);
// stu1.sayHi();
//
// var stu2=new Student("120");
// stu2.name="张三";
// stu2.age=20;
// stu2.sex="女";
// console.log(stu2.name,stu2.age,stu2.sex,stu2.weight,stu2.score);
// stu2.sayHi();
// var stu3=new Student("130");
// console.log(stu3.name,stu3.age,stu3.sex,stu3.weight,stu3.score);
// stu3.sayHi();
//为了数据共享,改变原型指向,做到了继承---通过改变原型指向实现的继承
//缺陷:因为改变原型指向的同时实现继承,直接初始化了属性,继承过来的属性的值都是一样的了,所以,这就是问题
//只能重新调用对象的属性进行重新赋值,
//解决方案:继承的时候,不用改变原型的指向,直接调用父级的构造函数的方式来为属性赋值就可以了------借用构造函数:把要继承的父级的构造函数拿过来,使用一下就可以了
//借用构造函数:构造函数名字.call(当前对象,属性,属性,属性....);
//解决了属性继承,并且值不重复的问题
//缺陷:父级类别中的方法不能继承
function Person(name, age, sex, weight) {
this.name = name;
this.age = age;
this.sex = sex;
this.weight = weight;
}
Person.prototype.sayHi = function () {
console.log("您好");
};
function Student(name,age,sex,weight,score) {
//借用构造函数
Person.call(this,name,age,sex,weight);
this.score = score;
}
var stu1 = new Student("小明",10,"男","10kg",100);
console.log(stu1.name, stu1.age, stu1.sex, stu1.weight, stu1.score);
var stu2 = new Student("小红",20,"女","20kg","120");
console.log(stu2.name, stu2.age, stu2.sex, stu2.weight, stu2.score);
var stu3 = new Student("小丽",30,"妖","30kg","130");
console.log(stu3.name, stu3.age, stu3.sex, stu3.weight, stu3.score);
</script>
</head>
<body>
</body>
</html>