javascript常用代碼

//建立XMLHttpRequest對象

function createXHR()
		{
			if(typeof XMLHttpRequest!="undefined")
			{
				//ie7以上瀏覽器
				return new XMLHttpRequest();
			}
			else if(typeof arguments.callee.activeXString!="string")
			{
				//ie7以下瀏覽器
			
				var 	versions=["MSXML2.XMLHttp.6.0","MSXML2.XMLHttp.3.0","MSXML2.XMLHttp"];
				for(var i=0 ,len=versions.length;i<len;i++)
				{
					try{
					
						var xhr=new ActiveXObject(versions[i]);
						arguments.callee.activeXString=versions[i];
						
						return xhr;
						}catch(ex)
						{
						//todo
						
						}
				}
			
			return new ActiveXObject(arguments.callee.activeXString);
			}
			else
			{
				throw new Error("No XHR object avaible!!!!!!");
			}
		}

添加事件處理函數

var EventUtil = {
    //create XHR
    function createXHR() {
        if (typeof XMLHttpRequest != "undefined") {
            return new XMLHttpRequest();
        }
        else if (typeof ActiveXObject != "undefined") {
            //ie6    
        }
    }
	//添加事件處理程序
    addHandler: function (element, type, handler) {
        if (element.addEventListener) {
            element.addEventListener(type, handler, false);
        } else if (element.attachEvent) {
            element.attachEvent("on" + type, handler);
        } else {
            element["on" + type] = handler;
        }
    },
    //刪除事件處理程序
    removeHandler: function (element, type, handler) {
        if (element.removeEventListener) {
            element.removeEventListener(type, handler, false);
        } else if (element.detachEvent) {
            element.detachEvent("on" + type, handler);
        } else {
            element["on" + type] = null;
        }
    },
    //獲取event對象
    getEvent: function () {
        if (event) return event;
        else return windows.event;
    },
    getTarget:function(event){
    	return event.target|| event.srcElement;
    },
    //阻止默認事件處理程序發生
    preventDefault:function(event){
    	if(event.preventDefault){
    		event.preventDefault();
    	}
    	else
    	{event.returnValue=false;}
     
    },
    //阻止冒泡
    stopPropagation:function(event){
    	if(event.stopPropagation)
    		event.stopPropagation();
    	 else
    	 {event.cancelBubble=true;}
    }
    
}