安全模式的工厂模式

var Factory = function(type,content){
        if (this instanceof Factory)
        {
            var s = new this[type](type,content);//运算符优先顺序
            return s;
        }else {
            return new Factory(type,content);
        }
    }

    Factory.prototype = {
        html:function(type,content){
            this.content = content;
            this.type = type;
            this.show = function(){
                console.log(this.type+this.content);
            }
        },
        php:function(type,content){
            this.content = content;
            this.type = type;
            this.show = function(){
                console.log(this.type+this.content);
            }
        }
    }
    var p1 = Factory('html','哪家强？');
    p1.show();
    var p2 = Factory('php','真的不错！');
    p2.show();

三个不同功能的按钮

 <body>
  <input type='button' value='btn1' name='click'/>
  <input type='button' value='btn2' name='mouseover'/>
  <input type='button' value='btn3' name='dblclick'/>
  <div id='div1'></div>
  <script>
    var Factory = function(type,element){
        if (this instanceof Factory)
        {
            var s = new this[type](element);
            return s;
        }else {
            return new Factory(type,element);
        }
    }
    
    Factory.prototype = {
        click:function(element){
            element.addEventListener('click',function(){
                oDiv.innerHTML = this.value;
            },false);
        },
        mouseover:function(element){
            element.addEventListener('mouseover',function(){
                oDiv.innerHTML = this.value;
            },false);
        },
        dblclick:function(element){
            element.addEventListener('dblclick',function(){
                oDiv.innerHTML = this.value;
            },false);
        }
    }

    var aBtn = document.getElementsByTagName('input'),
        oDiv = document.getElementById('div1');
    for (var i=0;i<aBtn.length ;i++ )
    {
        Factory(aBtn[i].name,aBtn[i]);
    }
    
  </script>
 </body>