js简单的年月联动实现代码

<select name="seltjyear">
</select>
<select name="seltjmonth">
</select>

function vyearmonth(yearobjid, monthobjid) {
var selyear = document.getelementbyid(yearobjid);
var selmonth = document.getelementbyid(monthobjid);
var mydate = new date(); //当前日期
var myyear = mydate.getfullyear(); //当前年
var mymonth = mydate.getmonth() + 1; //当前月
var yearmin = -2; //年份范围值，也当前年比较的差值
var yearmax = 10; //年份范围值，也当前年比较的差值

//begin年*******************************
selyear.options.add(new option("", ""));
for (var i = yearmin; i < yearmax; i++) {
var opt = new option(myyear + i, myyear + i);
selyear.options.add(opt);
}
//这里1-yearmin表示选中当前年，用1是因为开头有插入""
selyear.options.selectedindex = 1 - yearmin;
//end年*******************************

//begin月*******************************
selmonth.options.add(new option("", ""));
for (var i = 0; i < 12; i++) {
var opt = new option(i + 1, i + 1);
selmonth.options.add(opt);
}
//选中当前月
selmonth.options.selectedindex = mymonth;
//end月*******************************


selyear.onchange = function () {
if (this.value == "") {
selmonth.selectedindex = 0;
}
else {
if (selmonth.value == "") {
selmonth.selectedindex = mymonth;
}
}
};
}

vyearmonth('seltjyear', 'seltjmonth');