javascript实现图片滚动效果

           window.onload = rolloverInit;
           //加载窗体时触发事件
                                          
        function rolloverInit()...{
            for (var i=0; i<document.images.length; i++)...{
                if(document.images[i].parentNode.tagName=="A")...{
                    setupRollover(document.images[i]);
                }
            }
        }
        //对所有包含超级连接的图片执行滚动设置


        function setupRollover(thisImage)...{
            thisImage.outImage = new Image();
            thisImage.outImage.src = thisImage.src;
            thisImage.onmouseout = rollOut;

            thisImage.overImage = new Image();
            thisImage.overImage.src = thisImage.id + "_on.jpg";
            thisImage.onmouseover = rollOver;
        }
        //为图片设置了out和over两种模式和相应的图片，可根据需要实际添加或修改


        function rollOver()...{
            this.src = this.overImage.src;
        }
        
        function rollOut()...{
            this.src = this.outImage.src;
        }

 相应在HTML中要对脚本进行引用，同时需要滚动效果的图片应包含在超连接<a herf="..."></a>中