<select id="year">
<option value="">年</option>
</select>
<select id="month">
<option value="">月</option>
</select>
<select id="day">
<option value="">日</option>
</select>
<script>
var my_year;
var my_month;
var my_day;
// var my_year = 2013;
// var my_month = 5;
// var my_day = 31;
var myDate = new Date();
year = myDate.getFullYear();
var year_ctrl = $("#year");
for (var i = year; i >= 1900; i--) {
if (my_year === i) {
var option = $("<option selected='selected'>").text(i).val(i);
} else {
var option = $("<option>").text(i).val(i);
}
year_ctrl.append(option);
}
var month_ctrl = $("#month");
for (var i = 1; i <= 12; i++) {
if (my_month === i) {
var option = $("<option selected='selected'>").text(i).val(i);
} else {
var option = $("<option>").text(i).val(i);
}
month_ctrl.append(option);
}
makeDays();
$("#year").bind("change", function() {
makeDays();
});
$("#month").bind("change", function() {
makeDays();
});
function makeDays() {
var month_ctrl = $("#month");
var month = month_ctrl.val();
var year = $("#year").val();
var day = $("#day");
day.empty();
day.append(new Option("日", ""));
if (!year) {
month_ctrl.val("");
}
if (month && year) {
days = getDays(year, month);
for (var i = 1; i <= days; ++i) {
if (my_day === i) {
var option = $("<option selected='selected'>").text(i).val(i);
} else {
var option = $("<option>").text(i).val(i);
}
day.append(option);
}
}
}
function getDays(year, month)
{
var date = new Date(year, month, 0);
return date.getDate();
}
</script>
