function getStyle(obj,attr){
    if(obj.currentStyle){
        return obj.currentStyle[attr];
    }else{
        return getComputedStyle(obj,false)[attr];
    }
}

function addEvent(obj,type,fn){
    if(obj.attachEvent){
        obj.attachEvent('on'+type,function(){
            fn.call(this);
        });
    }else{
        obj.addEventListener(type,fn,false);
    }
}

function getClass(obj,claName){
    var oClass = obj.getElementsByTagName('*');
    for(var i=0;i<oClass.length;i++){
        if(oClass[i].className = claName){
            return oClass[i];
        }
    }
}

function Qiguo($arg){
    this.elements = [];
    switch(typeof $arg){
        case 'function' :
            addEvent(window,'load',$arg);
            break;
        case 'string' :
            switch($arg.substring(0,1)){
                case '#':
                    this.elements = document.getElementById($arg.substring(1));
                    break;
                case '.':
                    this.elements = getClass();
                    break;
                default:
                    this.elements = document.getElementsByTagName($arg);
            }
            break;
    }
}

Qiguo.prototype.click = function(fn){
    addEvent(this.elements,'click',fn);
    return this;
}

function $($arg){
    return new Qiguo($arg);
}

$(function(){
    $("#text").click(function(){
        alert('1123');
    })
})