單例模式實(shí)例對(duì)象優(yōu)點(diǎn)：可以保證實(shí)例對(duì)象的唯一性喂江，及數(shù)據(jù)的正確性
示例代碼：
model層（數(shù)據(jù)層）
//VipVo.ts:
class VipVo{
/** VIP等級(jí) */
public vip:number;
}
//VipMode.ts:
class VipModel{
private static _instance:VipModel;
private _vipVo:VipVo;
constructor(){
super();
}
public static getInstance():VipModel{
if(this._instance == null){
this._instance = new VipModel();
}
return this._instance;
}
public get vipVo():VipVo{
return this._vipVo;
}
public setVipVo(vo:VipVo):void{
this._vipVo = vo;
}
}
controller層（控制層）
//ImitVipMgr.ts
class ImitVipMgr {
//模擬的vip等級(jí)
private static vipLevel:number=2;
constructor() {
super();
}
private static _instance: ImitVipMgr;
public static getInstance(): ImitVipMgr {
if (this._instance == null) {
this._instance = new ImitVipMgr();
}
return this._instance;
}
public static setVip():void{
var vipVo: VipVo = new VipVo();
vipVo.vip = this.vipLevel++;
//實(shí)例VipModel對(duì)象琅翻，存值
VipModel.getInstance().setVipVo(vipVo);
}
}
view層（視圖層）
//第一步：實(shí)例ImitVipMgr對(duì)象渐扮，存值
var imitVipMgr:ImitVipMgr=ImitVipMgr.getInstance();
imitVipMgr.setVip();
//第二步：實(shí)例VipModel對(duì)象，取值
var vipMode:VipModel = VipModel.getInstance();
console.log(vipMode.vipVo.vip);
//輸出2
注意：
單例模式實(shí)例對(duì)象代碼
public static getInstance():VipModel{
if(this._instance == null){
this._instance = new VipModel();
}
return this._instance;
}
獲取對(duì)象代碼：
var vipMode:VipModel = VipModel.getInstance();
如果獲取對(duì)象的時(shí)候计贰，使用了new钦睡，比如：
var vipMode:VipModel =new VipModel();
console.log(vipMode.vipVo.vip);
//輸出undefined
因?yàn)閚ew一個(gè)實(shí)例，相當(dāng)于創(chuàng)建一塊內(nèi)存躁倒，與之前的對(duì)象不是同一個(gè)對(duì)象荞怒，所以屬性不存在
故洒琢，使用單例模式是保證對(duì)象唯一性和數(shù)據(jù)正確性的方法
