Question

var date1 = 怎样拆分为select二级列表联

Answer 1

在使用之前要清空的，和new差不多作用，你每次使用都是重新加载option，你现在是每次使用都是直接加的，并没有删除原先加载的，所以可能会造成每多点一次一级菜单，二级菜单就加一组，点的次数多了，二级菜单就太长了

Answer 2

<script type="text/javascript">
window.onload = function()
{
var now = new Date();
var currentYear = now.getFullYear();
var currentMonth = now.getMonth() + 1;
BindSelect(document.getElementById('year'), currentYear - 50, currentYear + 10, currentYear);
BindSelect(document.getElementById('month'), 1, 12, currentMonth);
}

function BindSelect(selectObj, startValue, endValue, selectedValue)
{
var i = 0;
for(var val = startValue; val <= endValue; val++)
{
selectObj.options.add(new Option(val , val));
if(val == selectedValue)selectObj.options[i].selected = true;
i++;
}
}
</script>
<select id="year"></select>年<select id="month"></select>月