设计模式

• 构造函数

function Person(name,age){
    
    this.name = name 
    this.age = age
}

Person.prototype.show = function(){
    console.log('My name is'+this.name,'My age is '+this.age)
}
var p1 = new Person('Lii',18)
console.log(p1.show())

• 混合模式(提取公用,节约内存)

var Person = function(name,age){
    this.name = name
    this.age = age
}
Person.prototype.sayHi=function(){
    console.log(this.name, this.age)
}
var p1 = new Person('Lii',18)
p1.sayHi()

• 模块模式(利用闭包来访问内部)

var Person = (function(){
    var name = 'xxx'
    var sayName = function(){
        console.log(name)
    }

    return {
        name:name,
        sayName:sayName
    }
    
})()
var p1 = Person
p1.sayName()

• 工厂模式

function person(name,age){
  var obj = {}
  obj.name = name
  obj.age = age
  return obj

}

var p1 = person('Lii',18)
cosole.log(p1.name,p1.age)

• 单利模式

var Person = !function(){
    var instance;
    function init(){
        return {

        }
    }

    return {
        createPerson:function(){
            if(!instance){
                instance = init()
            }
            return instace
        }
    }
}()

var p1 = Person.createPerson() 
var p2 = Person.createPerson() 

• 发布订阅模式

var xxx = (function(){
    var obj = {}//自定义事件存放

    var on = function(evt,handler){//push到数组
        obj[evt] = obj[evt] || [];
        obj[evt].push({
            handler:handler
        })
    }
    var fire = function(evt,args){//形成映射查找
        if(obj[!evt]) return;

        for(var i=0;i<obj[evt].length;i++){
            obj[evt][i].handler(args)
        }
    }

    return {
        on: on,
        fire: fire
    }
})()

xxx.on('m-coco',function(data){
    console.log('m-coco1')
})

xxx.on('m-coco',function(data){
    console.log('m-coco2')
})

xxx.fire('m-coco')

• 发布订阅demo

var Event = (function(){
    const obj = {}

    const on = (evt,handler)=>{
        obj[evt] = obj[evt] || []
        obj[evt].push({
            handler:handler
        }) 
    };
    const fire = (evt,params)=>{
        if(!obj[evt]) return
        for(var i=0;i<obj[evt].length;i++){
            obj[evt][i].handler(params)
        }
    };

    const off = (evt)=>{
        if(obj[evt]){
            delete obj[evt]
        }else{
            console.log('此'+evt+'无效')
        }
 }
        
   return {
        on: on,
        fire: fire,
        off: off
    }
})()

Event.on('change',(val)=>{
    console.log('change..now val is ' + val)
})

Event.fire('change','饥人谷')
Event.off('change')