JavaScript中的對(duì)象:
JavaScript中的主要對(duì)象有:
JavaScript的核心對(duì)象,瀏覽器對(duì)象,用戶自定義對(duì)象和文本對(duì)象等
JavaScript作為基于對(duì)象的編程語(yǔ)言,其對(duì)象實(shí)例采用構(gòu)造函數(shù)來(lái)創(chuàng)建.
每一個(gè)構(gòu)造函數(shù)包括一個(gè)對(duì)象原型,定義了每個(gè)對(duì)象包含的屬性和方法,對(duì)象是動(dòng)態(tài)的,表明對(duì)象實(shí)例的
屬性和方法是可以動(dòng)態(tài)添加刪除或修改的.

通過(guò)構(gòu)造方法來(lái)定義對(duì)象:
<script language="JavaScript" type="text/javascript">
<!--
//對(duì)象的構(gòu)造函數(shù)
function Test(iName,iAddress,iGrade,iNumber)
{
this.name=iName;
this.address=iAddress;
this.grade=iGrade;
this.number=iNumber;
this.information=showInformation;
}
//定義對(duì)象的方法
function showInformation()
{
statements ;
}
//生成對(duì)象的實(shí)例
var test = new Test('thtwin,'thtwinj2ee','th','thtwin') ;
-->
</script>

對(duì)過(guò)對(duì)象直接初始化的方法:
此方法通過(guò)直接初始化對(duì)象來(lái)創(chuàng)建自定義對(duì)象與定義對(duì)象的構(gòu)造函數(shù)方法不同的是,
該方法不需要生成引對(duì)象的實(shí)例.例如:
<script language="JavaScript" type="text/javascript">
<!--
//對(duì)象的構(gòu)造函數(shù)
//構(gòu)造嵌套的對(duì)象
var SchoolData={
code:"0123-456-789",
Tel:"0551-1234567",
Fax:"0551-7654321"
};
//構(gòu)造被嵌入的對(duì)象
var myTest={
name:"test",
address:"遼寧*葫蘆島",
grade:"test",
number:"13400",
//嵌套對(duì)象SchoolData
data:SchoolData,
information:showInformation
};
//定義對(duì)象的方法
function showInformation()
{
alert(this.data.code) ;
statements ;
}
-->
</script>
下面為調(diào)用上面對(duì)象的方法:
<form>
<input type="button" value="調(diào)試對(duì)象" onclick="myTest.information()">
</form>


更新對(duì)象中的方法或者屬性.如:

<script language="JavaScript" type="text/javascript">
<!--
//對(duì)象的構(gòu)造函數(shù)
function School(iName,iAddress,iGrade,iNumber)
{
this.name=iName;
this.address=iAddress;
this.grade=iGrade;
this.number=iNumber;
this.information=showInformation;
}
//定義對(duì)象的方法
function showInformation()
{
var msg="";
msg="通過(guò)原型給對(duì)象添加新屬性和新方法：\n\n"
msg+="原始屬性:\n";
msg+=" 機(jī)構(gòu)名稱 : "+this.name+" \n";
msg+=" 所在地址 : "+this.address +"\n";
msg+=" 教育層次 : "+this.grade +" \n";
msg+=" 在校人數(shù) : "+this.number+" \n\n";
msg+="新屬性:\n";
msg+=" 占地面積 : "+this.addAttributeOfArea+" \n";
msg+="新方法:\n";
msg+=" 方法返回 : "+this.addMethod+"\n";
window.alert(msg);
}
function MyMethod()
{
statements ;
}
//生成對(duì)象的實(shí)例
var test=new School("test","遼寧*葫蘆島","test","123000");
School.prototype.addAttributeOfArea="3000";
School.prototype.addMethod=MyMethod();
-->
</script>

JavaScript語(yǔ)言中所有對(duì)象都由Object對(duì)象派生,每個(gè)對(duì)象都有指定了其結(jié)構(gòu)的原型(prototype)屬性,
該屬性描述了該類型對(duì)象其有的代碼和數(shù)據(jù),可以通過(guò)對(duì)象的prototype屬性為對(duì)象動(dòng)態(tài)添加新屬性和新
方法

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