这篇文章将为大家详细讲解有关使用JavaScript怎么实现一个日期选择功能，文章内容质量较高，因此小编分享给大家做个参考，希望大家阅读完这篇文章后对相关知识有一定的了解。
具体如下：
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta charset="utf-8">
<title>javascript日期选择</title>
<style type="text/css">
option{
width:150px;
}
</style>
</head>
<body>
<!--<input type="hidden" value="window.location.href" />-->
<br />
<div id="dateOp">
<select id="selectYear" onchange="getDay()"></select>年
<select id="selectMonth" onchange="getDay()"></select>月
<select id="selectDay"></select>日
<input type="button" value="getdate" />
</div>
<script type="text/javascript">
//或得当前年月日
var date = new Date();
var year = date.getFullYear();
var month = date.getMonth() + 1;
var day = date.getDate();
var startYear = 2000;
var endYear = 2050;
var button = document.getElementsByTagName("input")[0];
//得到三个select项
var selectYearElement = document.getElementById("selectYear");
var selectMonthElement = document.getElementById("selectMonth");
var selectDayElement = document.getElementById("selectDay");
//selectYearElement.onchange = getDay();
//selectMonthElement.onchange = getDay();
//selectYearElement.addEventListener
getYear();
getMonth();
getDay();
//年份函数
function getYear() {
for (var i = startYear; i <= endYear; i++) {
var opYearElement = document.createElement("option");
var textElement = document.createTextNode(i);
opYearElement.appendChild(textElement);
opYearElement.value = i;
selectYearElement.appendChild(opYearElement);
}
//设置默认年份的值
selectYearElement.selectedIndex = year - startYear;
}
//月份函数
function getMonth() {
for (var i = 1; i <= 12; i++) {
var opMonthElement = document.createElement("option");
textMonth = document.createTextNode(i);
opMonthElement.appendChild(textMonth);
opMonthElement.value = i;
selectMonthElement.appendChild(opMonthElement);
}
//设置默认年份的值
selectMonthElement.selectedIndex = month - 1;
}
//日期函数
function getDay() {
var getSelectedYear = selectYearElement.selectedIndex + startYear;
var getSelectedMonth = selectMonthElement.selectedIndex + 1;
var flag = 0;
var selectDayElement = document.getElementById("selectDay");
if (selectDayElement.hasChildNodes()) {
var optionElements = selectDayElement.getElementsByTagName("option");
for (var i = 0; i < optionElements.length; i++) {
selectDayElement.removeChild(optionElements[0]);
//不知道为什么必须得自减一
i--;
}
}
else {
}
//得到闰年
if ((getSelectedYear % 4 == 0 && getSelectedYear % 100 != 0) || getSelectedYear % 400 == 0) {//得到闰年的年号
//alert("闰年");
//得到闰年大月份除二月以外
if ((getSelectedMonth <= 7 && getSelectedMonth % 2 == 1 && getSelectedMonth != 2) || (getSelectedMonth >= 8 && getSelectedMonth % 2 == 0)) {//得到大月
setDay(flag = 31);
}
else if (getSelectedMonth <= 7 && getSelectedMonth == 2) {
setDay(flag = 29);
}
else if ((getSelectedMonth <= 7 && getSelectedMonth % 2 == 0 && getSelectedMonth != 2) || (getSelectedMonth >= 8 && getSelectedMonth % 2 == 1)) {//得到小月份除二月以外
setDay(flag = 30);
}
}
//非闰年
else {
//alert("平年");
//得到平年大月份除二月以外
if ((getSelectedMonth <= 7 && getSelectedMonth % 2 == 1 && getSelectedMonth != 2) || (getSelectedMonth >= 8 && getSelectedMonth % 2 == 0)) {//得到大月
setDay(flag = 31);
}
else if (getSelectedMonth <= 7 && getSelectedMonth == 2) {
setDay(flag = 28);
}
else if ((getSelectedMonth <= 7 && getSelectedMonth % 2 == 0 && getSelectedMonth != 2) || (getSelectedMonth >= 8 && getSelectedMonth % 2 == 1)) {//得到小月份除二月以外
setDay(flag = 30);
}
}
}
//设置默认年份的值
selectDayElement.selectedIndex = day - 1;
function setDay(dayLength) {
for (var i = 1; i <= dayLength; i++) {
var opDayElement = document.createElement("option");
textMonth = document.createTextNode(i);
opDayElement.appendChild(textMonth);
opDayElement.value = i;
//alert(i);
selectDayElement.appendChild(opDayElement);
}
}
button.onclick = function () {
var getSelectedYear = selectYearElement.selectedIndex + startYear;
var getSelectedMonth = selectMonthElement.selectedIndex + 1;
var getSelectedDay = selectDayElement.selectedIndex + 1;
alert("当前选中的日期是：" + getSelectedYear + "年" + getSelectedMonth + "月" + getSelectedDay + "日")
}
//getDay
</script>
</body>
</html>关于使用JavaScript怎么实现一个日期选择功能就分享到这里了，希望以上内容可以对大家有一定的帮助，可以学到更多知识。如果觉得文章不错，可以把它分享出去让更多的人看到。