JavaScript 創建對象和構造類實現代碼
2024-05-06 14:14:30
供稿：網友
創建一個對象
Java代碼
代碼如下:
<script type="text/javaScript">
var newObject=new Object();
//創建一個對象
newObject.firstName="frank";
//增加一個firstName屬性
newObject.sayName=function(){
alert(this.firstName);
}
//添加一個sayName方法
//調用sayName方法
// newObject.sayName();
// newObject["sayName"]();
var FirstName=newObject["firstName"];
var whatFunction;
// if(whatVolume==1){
// whatFunction="sayName";
// }else if(whatVolume==2){
// whatFunction="sayLoudly"
// }
// newObject[whatFunction]();
function sayLoudly(){
alert(this.firstName.toUpperCase());
}
newObject.sayLoudly=sayLoudly;
//另一種方式添加方法
newObject["sayLoudly"]();
</script>
利用json（javaScript Object Notation）創建對象和上面同樣的效果。
Java代碼
代碼如下:
function sayLoudly(){
alert(this.firstName.toUpperCase());
}
var newObject={
firstName:"frank",
sayName:function(){alert(this.firstName);},
sayLoudly:sayLoudly
};
//也可以這樣
var newObject={
firstName:"frank",
sayName:function(){alert(this.firstName);},
sayLoudly:sayLoudly,
lastName:{
lastName:"ziggy",
sayName:function(){alert(this.lastName);}
}
};
newObject.lastName.sayName();
這樣也ok
Java代碼
代碼如下:
function sayLoudly(){
alert(this.name.toUpperCase());
}
function sayName(){
alert(this.name);
}
var newObject={
name:"frank",
sayName:sayName,
sayLoudly:sayLoudly,
lastName:{
name:"ziggy",
sayName:sayName
}
};
newObject.lastName.sayName();
JavaScript 中的類，還有構造方法。。。
Java代碼
代碼如下:
function newClass(){
alert("constructor");
this.firstName="frank";
this.sayName=function(){alert(this.firstName);}
// return this;
}
//var nc=newClass();
var nc=new newClass();
//nc.firstName="ziggy"; is ok
nc.sayName();
還可以這樣來構造類
Java代碼
代碼如下:
function newClass(){
this.firstName="frank";
}
newClass.prototype.sayName=function(){
alert(this.firstName);
}
var nc=new newClass();
nc.firstName="ziggy";
nc.sayName();
var nc2=new newClass();
nc2.sayName();
一般用prototypes來添加方法，這樣不管有多少個實例，在內存中只有一個sayName方法。
