发布于 2016-08-21 06:40:39 | 87 次阅读 | 评论: 0 | 来源: 网友投递
这里有新鲜出炉的Javascript教程,程序狗速度看过来!
JavaScript客户端脚本语言
Javascript 是一种由Netscape的LiveScript发展而来的原型化继承的基于对象的动态类型的区分大小写的客户端脚本语言,主要目的是为了解决服务器端语言,比如Perl,遗留的速度问题,为客户提供更流畅的浏览效果。
Object.create() 是什么?
Object.create(proto [, propertiesObject ]) 是E5中提出的一种新的对象创建方式,第一个参数是要继承的原型,如果不是一个子函数,可以传一个null,第二个参数是对象的属性描述符,这个参数是可选的。
例如:
function Car (desc) {
this.desc = desc;
this.color = "red";
}
Car.prototype = {
getInfo: function() {
return 'A ' + this.color + ' ' + this.desc + '.';
}
};
//instantiate object using the constructor function
var car = Object.create(Car.prototype);
car.color = "blue";
alert(car.getInfo());
结果为:A blue undefined.
1、propertiesObject 参数的详细解释:(默认都为false)
数据属性:
访问属性:
2、例子:直接看例子就知道怎么用。
<!DOCTYPE html>
<html>
<head>
<title>yupeng's document </title>
<meta charset="utf-8"/>
</head>
<body>
<script type="text/javascript">
var obj = {
a:function(){
console.log(100)
},
b:function(){
console.log(200)
},
c:function(){
console.log(300)
}
}
var newObj = {};
newObj = Object.create(obj,{
t1:{
value:'yupeng',
writable:true
},
bar: {
configurable: false,
get: function() { return bar; },
set: function(value) { bar=value }
}
})
console.log(newObj.a());
console.log(newObj.t1);
newObj.t1='yupeng1'
console.log(newObj.t1);
newObj.bar=201;
console.log(newObj.bar)
function Parent() { }
var parent = new Parent();
var child = Object.create(parent, {
dataDescriptor: {
value: "This property uses this string as its value.",
writable: true,
enumerable: true
},
accessorDescriptor: {
get: function () { return "I am returning: " + accessorDescriptor; },
set: function (val) { accessorDescriptor = val; },
configurable: true
}
});
child.accessorDescriptor = 'YUPENG';
console.log(child.accessorDescriptor);
var Car2 = function(){
this.name = 'aaaaaa'
} //this is an empty object, like {}
Car2.prototype = {
getInfo: function() {
return 'A ' + this.color + ' ' + this.desc + '.';
}
};
var newCar = new Car2();
var car2 = Object.create(newCar, {
//value properties
color: { writable: true, configurable:true, value: 'red' },
//concrete desc value
rawDesc: { writable: true, configurable:true, value: 'Porsche boxter' },
// data properties (assigned using getters and setters)
desc: {
configurable:true,
get: function () { return this.rawDesc.toUpperCase(); },
set: function (value) { this.rawDesc = value.toLowerCase(); }
}
});
car2.color = 'blue';
console.log(car2.getInfo());
car2.desc = "XXXXXXXX";
console.log(car2.getInfo());
console.log(car2.name);
</script>
</body>
</html>
结果为:
100
yupeng
yupeng1
201
I am returning: YUPENG
A blue PORSCHE BOXTER.
A blue XXXXXXXX.
aaaaaa
以上就是针对javascript一种新的对象创建方式Object.create()的详细介绍,希望对大家的学习有所帮助。