在javascript中创建并使用对象
<script>
var person = new Object();
person.name = "lgx";
person.sex = "man";
person.age = 24;
person.sayhello = function ()
{
alert("hello my name is"+this.name);
}
</script> <body>
<script>
var person = new Object();
person.name = "lgx";
person.sex = "man";
person.age = 24;
person.sayhello = function ()
{
alert("hello my name is"+this.name);
}
</script> <body>
<script>
person.sayhello();
使用JSON（javascript Object Notation）
<script type=text/javascript>
var person=
{
name:"lgx", sex:"man", age:21,
sayHello:function(word){ alert(word+this.name);
}
} </script>
<form id="Form1" method="post" runat="server"> <FONT face="宋体"></FONT> <script type=text/javascript> //person.sayHello('haha:'); </script> </form>定义复杂对象
var myLibrary=
{
location:"my house",
keywords:["row vegetables","turnip","tedium"],
books:[
{title:"The title",
authors:[
{name:"jim brow",age:18},
{name:"xxxx",age:13}
]
}
]
}
{
location:"my house",
keywords:["row vegetables","turnip","tedium"],
books:[
{title:"The title",
authors:[
{name:"jim brow",age:18},
{name:"xxxx",age:13}
]
}
]
}
使用prototype声明对象属性和方法
function MyObject(name,size)
{
this.name = name;
this.size = size;
}
MyObject.prototype.tellsize = function()
{
alert("size of"+this.name+"is"+this.size);
}
var myObject = new MyObject("tiddles","7.5 meters");
myObject.tellsize();
{
this.name = name;
this.size = size;
}
MyObject.prototype.tellsize = function()
{
alert("size of"+this.name+"is"+this.size);
}
var myObject = new MyObject("tiddles","7.5 meters");
myObject.tellsize();
需要注意代码执行顺序，只有在构造函数声明之后才能引用其prototype属性，而且
对象从prototype所获得的属性和方法，必须声明在调用构造函数创建对象之前。
用prorotype实现继承
function Vehicle()
{
}
Vehicle.prototype.wheelCount =4;
Vehicle.prototype.curbWeightInPounds = 4000;
Vehicle.prototype.refuel = function()
{
return "Refueling Vehicle with regular 87 octane gasoline";
}
Vehicle.prototype.mainTasks = function()
{
return "Driving to work ,school ,and the grocery store";
}
function SportsCar()
{
}
SportsCar.prototype = new Vehicle();
SportsCar.prototype.curbWeightInPounds = 3000;
SportsCar.prototype.refuel = function ()
{
return "Refueling SportsCar with premium 94 octane gasoline";
}
SportsCar.prototype.mainTasks = function(){
return "Spirited driving ,looking good ,driving to the beach";
}
function discribe(vehicle)
{
var str = "";
str = "\n\nNumber of wheels:"+ vehicle.wheelCount;
str += " Crub Weight: "+vehicle.curbWeightInPounds;
str += "\n\n Refuel Method:"+vehicle.refuel();
str += "\n\n Main Tasks:" + vehicle.mainTasks();
document.getElementById("Info").innerText+=str;
}
function createVehicle()
{
var vehicle = new Vehicle();
discribe(vehicle);
}
function createSportsCar()
{
var sportCar = new SportsCar();
discribe(sportCar);
}
{
}
Vehicle.prototype.wheelCount =4;
Vehicle.prototype.curbWeightInPounds = 4000;
Vehicle.prototype.refuel = function()
{
return "Refueling Vehicle with regular 87 octane gasoline";
}
Vehicle.prototype.mainTasks = function()
{
return "Driving to work ,school ,and the grocery store";
}
function SportsCar()
{
}
SportsCar.prototype = new Vehicle();
SportsCar.prototype.curbWeightInPounds = 3000;
SportsCar.prototype.refuel = function ()
{
return "Refueling SportsCar with premium 94 octane gasoline";
}
SportsCar.prototype.mainTasks = function(){
return "Spirited driving ,looking good ,driving to the beach";
}
function discribe(vehicle)
{
var str = "";
str = "\n\nNumber of wheels:"+ vehicle.wheelCount;
str += " Crub Weight: "+vehicle.curbWeightInPounds;
str += "\n\n Refuel Method:"+vehicle.refuel();
str += "\n\n Main Tasks:" + vehicle.mainTasks();
document.getElementById("Info").innerText+=str;
}
function createVehicle()
{
var vehicle = new Vehicle();
discribe(vehicle);
}
function createSportsCar()
{
var sportCar = new SportsCar();
discribe(sportCar);
}
对象反射
检测一个对象是否有某个属性
if(typeof(MyObject.somePrototype)!="undefined")
检测对象某个属性的类型
if(myObj instanceof Array)设置剪切板内容
copyLink:function()
{
var link = window.location.href;
var endIndex = link.lastIndexOf("/")+1;
var host = link.substring(0,endIndex)+"bbs_big.aspx?topicId="+this.NewShowingTopicId;
window.clipboardData.setData("Text",host);
alert("已将链接["+host+"]复制到剪切板,粘贴即可!");
}
{
var link = window.location.href;
var endIndex = link.lastIndexOf("/")+1;
var host = link.substring(0,endIndex)+"bbs_big.aspx?topicId="+this.NewShowingTopicId;
window.clipboardData.setData("Text",host);
alert("已将链接["+host+"]复制到剪切板,粘贴即可!");
}
get object position
Number.prototype.NaN0=function(){return isNaN(this)?0:this;}
function getPosition(e){
var left = 0;
var top = 0;
while (e.offsetParent){
left += e.offsetLeft + (e.currentStyle?(parseInt(e.currentStyle.borderLeftWidth)).NaN0():0);
top += e.offsetTop + (e.currentStyle?(parseInt(e.currentStyle.borderTopWidth)).NaN0():0);
e = e.offsetParent;
}
left += e.offsetLeft + (e.currentStyle?(parseInt(e.currentStyle.borderLeftWidth)).NaN0():0);
top += e.offsetTop + (e.currentStyle?(parseInt(e.currentStyle.borderTopWidth)).NaN0():0);
return {x:left, y:top};
}
function getPosition(e){
var left = 0;
var top = 0;
while (e.offsetParent){
left += e.offsetLeft + (e.currentStyle?(parseInt(e.currentStyle.borderLeftWidth)).NaN0():0);
top += e.offsetTop + (e.currentStyle?(parseInt(e.currentStyle.borderTopWidth)).NaN0():0);
e = e.offsetParent;
}
left += e.offsetLeft + (e.currentStyle?(parseInt(e.currentStyle.borderLeftWidth)).NaN0():0);
top += e.offsetTop + (e.currentStyle?(parseInt(e.currentStyle.borderTopWidth)).NaN0():0);
return {x:left, y:top};
}
将函数作为一个对象的方法调用
Function.apply()
function.apply(thisobj,args)
function.apply(thisobj,args)
thisobj:调用函数的对象，在函数主体中，thisobj是关键字this的值；
args：一个数组，他的值是要传递给function的参数值
------------------
将函数作为对象的方法调用
Function.call()
function.call(thisobj,arg.)
function.call(thisobj,arg
.)thisobj:调用function的对象，在函数主体中，是this关键字的值；
args：任意多个参数，这些参数传递给函数function