JS年月日三级联动下拉列表

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>年/月/日三级联动JS代码</title>

<style>
body {
margin: 0px;
padding: 50px;
font-size: 12px;
}
#year, #month, #day{
60px;
margin-right: 3px;
}
</style>
<script>
var $ = function(id) { return 'string' == typeof id ? document.getElementById(id) : id; };
var Extend = function(destination, source) {
for(var pro in source) {
destination[pro] = source[pro];
}
return destination;
}
var addEvent = function(obj, type, fn) {
if(obj.addEventListener) {
obj.addEventListener(type, fn, false);
return true;
}else if(obj.attachEvent) {
obj['e'+type+fn] = fn;
obj[type+fn] = function(){
obj['e'+type+fn](window.event);
}
obj.attachEvent('on'+type, obj[type+fn]);
return true;
}
return false;
}

function DateSelector(idYear, idMonth, idDay, options) {
var D = new Date();
this.year = $(idYear);
this.month = $(idMonth);
this.day = $(idDay);
this.nowYear = D.getFullYear();
this.nowMonth = D.getMonth() + 1;
this.nowDate = D.getDate();
Extend(this, this.setOptions(options));
};
DateSelector.prototype = {
setOptions: function(options){
// 默认项
this.options = {
floorYear: 100, // 距当前年份前5年
ceilYear: 0, // 距当前年份后7年
onStart: function(){}, // 前置事件
onEnd: function(){} // 结束事件
};
return Extend(this.options, options || {});
},
//创建option
createOption: function(container, start, end, sign){
sign = sign || start;
var _num = parseInt(end-start+1, 10); container.options.length = _num;
for(var i = 0; i < _num; i++) {
container.options[i].text = container.options[i].value = start + i;
}
container.selectedIndex = (sign-start >= _num ? _num-1 : sign-start);
},
// 获取年月对应的日期数
getDate: function(y, m){
return new Date(y, m, 0).getDate();
},
// 获取option-text
getSelText: function(sel) {
return sel.options[sel.selectedIndex].text;
},
// 年月日切换
changeDate: function(bindO){
var _this = this;
addEvent(bindO, 'change', function(){
var y = _this.getSelText(_this.year), m = _this.getSelText(_this.month), d = _this.getSelText(_this.day);
_this.createOption(_this.day, 1, _this.getDate(y, m), d);
_this.onEnd();
});

},
// 绑定相应事件
bindEvents: function(){
var _this = this;
this.changeDate(this.year); this.changeDate(this.month);
addEvent(this.day, 'change', function(){ _this.onEnd(); });
},
// 代码初始化
init: function(){
var _startYear = parseInt(this.nowYear - this.floorYear, 10);
var _endYear = parseInt(this.nowYear + this.ceilYear, 10);
var _endDate = this.getDate(this.nowYear, this.nowMonth, 0);
this.createOption(this.year, _startYear, _endYear, this.nowYear);
this.createOption(this.month, 1, 12, this.nowMonth);
this.createOption(this.day, 1, _endDate, this.nowDate);
this.bindEvents();
this.onStart();
}
};
</script>
</head>
<body>

<select id="year"></select><select id="month"></select><select id="day"></select>
<span id="info"></span>
<script>
var dateSelector = new DateSelector('year', 'month', 'day');
dateSelector.onStart = dateSelector.onEnd = function(){
$('info').innerHTML = this.getSelText(this.year) + '年' +
('0' + this.getSelText(this.month)).slice(-2) + '月' +
('0' + this.getSelText(this.day)).slice(-2) + '日';
}
dateSelector.init();
</script>
</body>
</html>