jQuery
     

 

分离构造器

http://www.imooc.com/code/3398

var $$ = ajQuery = function(selector) {        this.selector = selector;        return this    }    ajQuery.fn = ajQuery.prototype = {        selectorName:function(){            return this.selector;        },        constructor: ajQuery    }    var a = new $$('aaa');  //实例化    console.log(a);    var name =  a.selectorName();//aaa //得到选择器名字    console.log(name);

改进，去掉new

ar $$ = ajQuery = function(selector) {        console.log(this);        if(!(this instanceof ajQuery)){            return new ajQuery(selector);        }        this.selector = selector;        return this;    }    ajQuery.fn = ajQuery.prototype = {        selectorName:function(){            return this.selector;        },        constructor: ajQuery    }    var a = $$('aaa');  //实例化    console.log(a);    var name =  a.selectorName();//aaa //得到选择器名字    console.log(name);