整理历史知识-设计模式-单例模式

// 单个例子的模式 demo1

function singleCase (name){

this.name = name;

}

singleCase.prototype.sayHi = function(){

alert(this.name);

}

let getInstance = (function(){

var instance = null;

return function(name) {

if(!instance) { //相当于一个一次性阀门,只能实例化一次

instance = new singleCase(name);

}

return instance;

}

})();

let one = getInstance("one");

let two = getInstance("two");

 

// 单例模式 demo2

 

function Single (name){

this.name = name;

}

Single.prototype.say = function(){

alert(12);

}

Single.getInstance = function (...args){

if(this.instance){

return this.instance;

}

this.instance = new Single(...args)

return this.instance;

}

let a1 = Single.getInstance("a1")

let a2 = Single.getInstance("a2")