function autoplay() {
index++;
if (index >= list.length) {
index = 0;
}
changeoption(index);
}
function changeoption( curIndex){
for (var j = 0; j < list.length; j++) {
list[j].className = ""
}
list[curIndex].className = "on";
pic.style.marginTop = -170 * (curIndex) + "px";
index = curIndex;
}
function tab() {
for (var i = 0; i < list.length; i++) {
list[i].id = i;
list[i].onmouseover = function () {
clearInterval(timer);
changeoption(this.id);
}
list[i].onmouseout = function () {
clearInterval(timer);
timer = setInterval(autoplay, 2000)
}
}
clearInterval(timer);
timer = setInterval(autoplay, 2000)
}
tab();
}
