无缝滚动改进版支持上下左右滚动（封装成函数）

复制代码 代码如下:



   
   
   
    *{margin:0;padding:0;}
    li{list-style:none;}
    img{border:0;}
    #scroll{width:178px;margin:50px auto;position:relative;}
    .btn{display:block;width:27px;height:27px;position:absolute;left:75px;}
    .up{background:url(images/up.gif);top:0;}
    .down{background:url(images/down.gif);top:490px;}
    .content{height:440px;overflow:hidden;position:relative;top:40px;}
    .content ul{position:absolute;top:0;left:0;}
    .content li{height:110px;}
   


   
       
       
       
           

复制代码 代码如下:

function scroll(direction,speed,iTime){
    var oDiv = document.getElementById('scroll');
    var oUl = oDiv.getElementsByTagName('ul')[0];
    var aLi = oDiv.getElementsByTagName('li');
    var aBtn = oDiv.getElementsByTagName('a');
    var timer = null;
    var iSpeed = 0;
    var flag = true;    //判断水平移动还是垂直移动

    oUl.innerHTML += oUl.innerHTML;

    switch(direction){
        case 'left':
            iSpeed = -speed;
            oUl.style.width = aLi[0].offsetWidth * aLi.length + 'px';
            flag = true;
            break;
        case 'right':
            iSpeed = speed;
            oUl.style.width = aLi[0].offsetWidth * aLi.length + 'px';
            flag = true;
            break;
        case 'top':
            iSpeed = -speed;
            flag = false;
            break;
        case 'bottom':
            iSpeed = speed;
            flag = false;
            break;
    };

    setTimeout(move,iTime);

    //左按钮和上按钮
    aBtn[0].onclick = function(){
        clearInterval(timer);
        iSpeed = -speed;
        move();
    };

    //右按钮和下按钮
    aBtn[1].onclick = function(){
        clearInterval(timer);
        iSpeed = speed;
        move();
    };

    oUl.onmouseover = function(){
        clearInterval(timer);
    };

    oUl.onmouseout = function(){
        move();
    };

    function move(){   
        timer = setInterval(function(){
            if(flag){
                oUl.style.left = oUl.offsetLeft + iSpeed + 'px';
                if(oUl.offsetLeft < -oUl.offsetWidth / 2){
                    oUl.style.left = '0';
                }else if(oUl.offsetLeft > 0){
                    oUl.style.left = - oUl.offsetWidth / 2 + 'px';
                }
            }else{
                oUl.style.top = oUl.offsetTop + iSpeed + 'px';
                if(oUl.offsetTop <= - oUl.offsetHeight / 2){
                    oUl.style.top = '0';
                }else if(oUl.offsetTop >= 0){
                    oUl.style.top = - oUl.offsetHeight / 2 + 'px';
                };
            };
        },30);
    };
};

需要注意的是：html 结构必须要像上面的结构一样。