// JavaScript Document

 //filter:revealTrans(transition=23,duration=0.5)

        var varImageName = 1;
        var varSecond = 2;

        //改变背景图片
        function ChageImage() {
            if (varImageName < 4) {
                varImageName++;
            }
            else if (varImageName == 4) {
                varImageName = 1;
            }

            var varRan = parseInt(Math.random() * 20) + parseInt(1);
            
            //1.设置滤镜
            document.getElementById("divAdShow").style.filter = "revealTrans(transition=" + varRan + ",duration=" + varSecond + ")";
            //2.接受动作
            document.getElementById("divAdShow").filters.revealTrans.apply();
            document.getElementById("divAdShow").style.backgroundImage = "url(img/" + varImageName + ".jpg)";
            //3.使用滤镜的效果来执行动作
            document.getElementById("divAdShow").filters.revealTrans.play();
            
            //切换数字
            ChageAdNumber();
        }

        //当鼠标移动到广告上，停止切换
        function StopChangeImage() {
            clearInterval(varIntervalID);
        }
        
        //计时器编号
        var varIntervalID;

        //启动变化图片计时器
        function StartAd() {
            varIntervalID = setInterval("ChageImage()", varSecond * 1000*2);
        }

        //跳转到广告页面
        function GoToAdPage() {
            window.open("imgNews.aspx");
        }
        
        //当图片切换的时候，对应的数字也切换
        function ChageAdNumber() {
            //1.还原所有数字背景色
            document.getElementById("div1").style.backgroundImage = "";
            document.getElementById("div2").style.backgroundImage = "";
            document.getElementById("div3").style.backgroundImage = "";
            document.getElementById("div4").style.backgroundImage = "";
            //2.切换背景色
            document.getElementById("div" + varImageName).style.backgroundImage = "url(img/bg2.gif)";
        }

        //当鼠标移动到某一个数字上，显示该数字对应的广告
        //val：表示当前你移动到的div的ID
        function ShowMoveOnImage(val) {
            //截取出编号
            var varImage = val.substr(3);
            
            //1.还原所有数字背景色
            document.getElementById("div1").style.backgroundImage = "";
            document.getElementById("div2").style.backgroundImage = "";
            document.getElementById("div3").style.backgroundImage = "";
            document.getElementById("div4").style.backgroundImage = "";
            //2.切换背景色
            document.getElementById(val).style.backgroundImage = "url(img/bg2.gif)";
            //3.切换图片
            document.getElementById("divAdShow").style.backgroundImage = "url(img/" + varImage + ".jpg)";
            //4.设置图片的名字
            varImageName = varImage;
        }