超简单图片切换

    <script language =javascript >
        var curIndex=0;
        //时间间隔 单位毫秒
        var timeInterval=5000;
        var arr=new Array();
        arr[0]="about.jpg";
        arr[1]="about1.jpg";

        setInterval(changeImg,timeInterval);
        function changeImg()
        {

            var obj=document.getElementById("showpic");
            if (curIndex==arr.length-1)
            {
                curIndex=0;
            }
            else
            {
                curIndex+=1;
            }

            obj.style.background = "url(images/"+arr[curIndex]+") no-repeat center center / 100% 100%";
        }

    </script>

<div  id="showpic"> </div>