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js中数据类型，对象，构造函数详解

零下一度

Jul 02, 2017 am 09:20 AM

javascriptjs

JavaScript数据类型，对象，构造函数，原型对象，初识原型链，对象继承

一.单词部分

①object父类②constructor构造函数③instance实例④call调用

⑤apply应用⑥combination组合⑦inheritance继承

二.预习部分

1.简述创建对象的两种方法，以及两者的区别

new 和字面量赋值

前者要用点.添加属性和方法

后者直接调用

2.简述使用构造函数创建实例的步骤

①创建一个新对象

②将构造函数的作用域赋值给新对象

③执行构造函数代码块

④返回新对象

3.简述原型链在继承中的作用

它是实现继承的主要方法

三.上机部分

1.创建person对象


	lang="en">

	charset="UTF-8">
	创建person对象<span class="html-tag">




	id="aa">
	<script> </span></td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var createTi=document.createElement("p");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var person=new Object();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">person.name="郎晓明";</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">person.age="38";</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">person.job="中国内地男演员、歌手";</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">person.address="中国北京海淀区";</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">person.info=function () {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var strr="姓名："+this.name+"<br/>年龄："+this.age+"<br/>工作："+this.job+"<br/>住址："+this.address;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">//document.write(strr);</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">document.getElementById("aa").innerHTML=strr;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">person.info();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content"><span class="html-tag"></script>

2.创建person构造函数


	lang="en">

	charset="UTF-8">
	上机练习二<span class="html-tag">


	id="aa">
	<script> </span></td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">function Person(name,age,job,address) {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.name=name;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.age=age;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.job=job;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.address=address;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.show=function() {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var createTi=document.createElement("p");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var strr="姓名："+this.name+"<br/>年龄："+this.age+"<br/>工作："+this.job+"<br/>住址："+this.address;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">document.getElementById("aa").innerHTML=strr;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">function Pers(){</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content"> </td> </tr> <tr> <td class="line-number"> </td> <td class="line-content"> </td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">//var newper=new Person("郎晓明","38","中国内地男演员、歌手","中国北京海淀区");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">Pers.prototype.name1="陈东";</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">Pers.prototype.age1="20";</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">Pers.prototype.job1="IT";</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">Pers.prototype.address1="河南省";</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">Pers.prototype.showinn=function () {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var createTi=document.createElement("p");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var strrr="姓名："+this.name1+"<br/>年龄："+this.age1+"<br/>工作："+this.job1+"<br/>住址："+this.address1;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">document.getElementById("aa").innerHTML=strrr;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var one=new Pers();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">one.showinn();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">//newper.show();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content"><span class="html-tag"></script>

3.创建person对象原型链


	lang="en">

	charset="UTF-8">
	上机练习三<span class="html-tag">


	id="aa">
	<script> </span></td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">function Person(nation,skinColor) {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.nation=nation;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.skinColor=skinColor;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var aaa=document.getElementById("aa");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.shownation=function () {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var createTi=document.createElement("p");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var st="民族："+this.nation;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">createTi.innerHTML=st;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">aaa.appendChild(createTi)</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.showskin=function () {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var createTi1=document.createElement("p");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var st1="肤色："+this.skinColor;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">createTi1.innerHTML=st1;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">aaa.appendChild(createTi1);</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">function Woman() {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">Person.call(this,"满族","黑色");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.sex="女";</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var sexa=document.getElementById("aa");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content"> </td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">//Woman.prototype=new Person("汉族","黄色");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">Woman.prototype.showsex=function () {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var createTi3=document.createElement("p");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var st3="性别："+this.sex;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">createTi3.innerHTML=st3;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">sexa.appendChild(createTi3);</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content"> </td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">//var per1=new Person("汉族","黄色");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var wo=new Woman();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content"> </td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">wo.shownation();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">wo.showskin();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">wo.showsex();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content"><span class="html-tag"></script>

4.创建继承person的student子类


	lang="en">

	charset="UTF-8">
	上机练习四<span class="html-tag">


	id="aa">
	<script> </span></td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">function Person(name,chinese,math) {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.name=name;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.chinese=chinese;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.math=math;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var aaa=document.getElementById("aa");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.showname=function () {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var createTi=document.createElement("p");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var st="姓名："+this.name;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">createTi.innerHTML=st;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">aaa.appendChild(createTi)</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.showchinese=function () {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var createTi1=document.createElement("p");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var st1="语文："+this.chinese;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">createTi1.innerHTML=st1;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">aaa.appendChild(createTi1);</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.showmath=function () {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var createTi2=document.createElement("p");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var st2="数学："+this.math;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">createTi2.innerHTML=st2;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">aaa.appendChild(createTi2);</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">function Student() {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">Person.call(this,"少君","56","96");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">this.age="19";</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var sexa=document.getElementById("aa");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content"> </td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">//Student.prototype=new Person("陈东","88","99");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">Student.prototype.showage=function () {</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var createTi3=document.createElement("p");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var st3="年龄："+this.age;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">createTi3.innerHTML=st3;</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">sexa.appendChild(createTi3);</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">}</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content"> </td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">//var per1=new Person("汉族","黄色");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">var stu=new Student();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">stu.showname();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">stu.showchinese();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">stu.showmath();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">stu.showage();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">/var ncm = new Person("陈东","88","99");</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">ncm.showname();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">ncm.showchinese();</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content">ncm.showmath();/</td> </tr> <tr> <td class="line-number"> </td> <td class="line-content"><span class="html-tag"></script>

四.总结

1.对象分为内置对象和自定义对象

2.原型链是实现继承的主要方法

3.组合继承的思路是使用原型链实现对原型属性和方法的继承

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