js构造函数，成员函数详解
对象之成员函数：
对象不仅只有属性，还要有行为（函数）
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script language="JavaScript" type="text/javascript">
function Person(name, age) {
//传递实参初始化属性
this.name = name;
this.age = age;
// 这就是一个公开的函数，这样的话浪费资源
this.show = function() {
document.write("名字=" + this.name + " " + "年龄=" + this.age + "<br/>");
}
this.add = function() {
var res = 0;
for(var i = 1; i <= 1000; i++) {
res += i;
}
return res;
}
}
var p1 = new Person("宋江", 90);
p1.show();
var p2 = new Person("李逵", 78);
p2.show();
document.write("res=" + p1.add());
</script>
</head>
<body>
</body>
</html>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script language="JavaScript" type="text/javascript">
function Person(name, age) {
//传递实参初始化属性
this.name = name;
this.age = age;
// 这就是一个公开的函数，这样的话浪费资源
this.add = function() {
var res = 0;
for(var i = 1; i <= 1000; i++) {
res += i;
}
return res;
}
}
function show(){
document.write("名字=" + this.name + " " + "年龄=" + this.age + "<br/>");
}
var p1 = new Person("宋江", 90);
//函数功能传递
p1.abc=show;
p1.abc();
//调用二
p1.bcd=function show1(){
document.write("名字"+this.name);
}
p1.bcd();
</script>
</head>
<body>
</body>
</html>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script language="JavaScript" type="text/javascript">
function Person(){
this.name="abc";
this.age=900;
this.abc=function(v1,v2){
document.write(this.name+" "+this.age+" "+v1+" "+v2+"<br/>");
}
}
var p1=new Person();
p1.abc();
p1.abc("背景","天津");
var p2=new Person();
p2.abc();
p2.abc("南京","东京");
</script>
</head>
<body>
</body>
</html>
使用prototype去绑定一个函数给shout，直接绑定给类，不需要创建对象时创建新的函数属性
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<script language="JavaScript" type="text/javascript">
function dog() {}
var dog1 = new dog();
dog.prototype.shout = function() {
document.write("小狗" + "<br/>");
}
dog1.shout();
var dog2 = new dog();
dog2.shout();
//判定是否为同一个函数
document.write(dog1.shout == dog2.shout);
</script>
</head>
<body>
</body>
</html>
通过==符号可以判断地址是否相等
2019.5.28
面向对象的深入学习：
函数可以作为一个属性：
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<link href="css/game.css" type="text/css" rel="stylesheet" />
<script language="JavaScript" type="text/javascript">
function jisuan(num1, num2, oper) {
if(oper == "+") {
return num1 + num2;
} else if(oper == "-") {
return num1 - num2;
} else return num1 * num2;
}
function Person(name, age, fun) {
this.name = name;
this.age = age;
this.myfun = fun;
}
var p1 = new Person("aa", 9, jisuan);
window.alert(p1.name);
window.alert(p1.myfun(89, 90, "+"));
</script>
</head>
<body>
</body>
</html>
创建对象的有一种形式:,如果一个对象比较简单可以直接创建;
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<link href="css/game.css" type="text/css" rel="stylesheet" />
<script language="JavaScript" type="text/javascript">
var dog = {
name: "小狗",
age: 8,
fun1:function(){
window.alert("hello,world!");
},
fun1:function(){
window.alert("okokok");
}
};
window.alert(dog.constructor);
window.alert(dog.name + dog.age);
dog.fun1();
</script>
</head>
<body>
</body>
</html>
类似于test.call(dog);的调用方法，调用对象实例
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<link href="css/game.css" type="text/css" rel="stylesheet" />
<script language="JavaScript" type="text/javascript">
var dog = {
name: "小狗",
age: 8
};
function test(){
window.alert(this.name);
}
test();
var name="shunping";
window.test();
test.call(dog);
</script>
</head>
<body>
</body>
</html>
for in 的用法
eg:循环列举出dog的属性
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<link href="css/game.css" type="text/css" rel="stylesheet" />
<script language="JavaScript" type="text/javascript">
var dog = {
name: "小狗",
age: 8,
sayHello:function(a,b){
window.alter("结果="+(a+b));
}
};
for(var key in dog){
window.alert(dog[key]);
}
</script>
</head>
<body>
</body>
</html>
遍历window的属性
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<link href="css/game.css" type="text/css" rel="stylesheet" />
<script language="JavaScript" type="text/javascript">
for(var key in window){
document.write(key+":"+window[key]+"<br/>");
}
</script>
</head>
<body>
</body>
</html>
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