//轮播图
window.onload=function(){
    var wrap=document.getelementbyid('lbt-wrap'),
    pic=document.getelementbyid('pic').getelementsbytagname("li"),
    list=document.getelementbyid('list').getelementsbytagname('li'),
    index=0,
    timer=null;
    
    // 定义并调用自动播放函数
    timer = setinterval(autoplay, 3000);
    
    // 鼠标划过整个容器时停止自动播放
    wrap.onmouseover = function () {
    clearinterval(timer);
    }
    
    // 鼠标离开整个容器时继续播放至下一张
    wrap.onmouseout = function () {
    timer = setinterval(autoplay, 3000);
    }
    // 遍历所有数字导航实现划过切换至对应的图片
    for (var i = 0; i < list.length; i++) {
    list[i].onmouseover = function () {
    clearinterval(timer);
    index = this.innertext - 1;
    changepic(index);
    };
    };
    
    function autoplay () {
    if (++index >= pic.length) index = 0;
    changepic(index);
    }
    
    // 定义图片切换函数
    function changepic (curindex) {
    for (var i = 0; i < pic.length; ++i) {
    pic[i].style.display = "none";
    list[i].classname = "";
    }
    pic[curindex].style.display = "block";
    list[curindex].classname = "on";
    }
    
    };