js日期函数

对日期的处理，date类型和字符串类型的相互转换，日期合法性验证
Date.prototype.isLeapYear 判断闰年
Date.prototype.toFormat 日期转成format格式字符串
Date.prototype.DateAdd 日期计算
Date.prototype.DateDiff 比较日期差
Date.prototype.toString 日期转字符串
Date.prototype.toArray 日期分割为数组
Date.prototype.DatePart 取日期的部分信息
Date.prototype.MaxDayOfDate 取日期所在月的最大天数
Date.prototype.WeekNumOfYear 判断日期所在年的第几周
StringToDate 字符串转日期型
IsValidDate 验证日期有效性
CheckDateTime 完整日期时间检查
daysBetween 日期天数差

//---------------------------------------------------
//日期转成format格式字符串
//---------------------------------------------------
Date.prototype.toFormat(date, format) {
var fmt = "yyyy-MM-dd";
if (format){
fmt = format;
}
var o = {
"M+" : date.getMonth()+1,                 //月份
"d+" : date.getDate(),                    //日
"h+" : date.getHours(),                   //小时
"m+" : date.getMinutes(),                 //分
"s+" : date.getSeconds(),                 //秒
"q+" : Math.floor((date.getMonth()+3)/3), //季度
"S"  : date.getMilliseconds()             //毫秒
};
if(/(y+)/.test(fmt))
fmt=fmt.replace(RegExp.$1, (date.getFullYear()+"").substr(4 - RegExp.$1.length));
for(var k in o)
if(new RegExp("("+ k +")").test(fmt))
fmt = fmt.replace(RegExp.$1, (RegExp.$1.length==1) ? (o[k]) : (("00"+ o[k]).substr((""+ o[k]).length)));
return fmt;
}
//---------------------------------------------------
// 判断闰年
//---------------------------------------------------
Date.prototype.isLeapYear = function()
{
return (0==this.getYear()%4&&((this.getYear()%100!=0)||(this.getYear()%400==0)));
}

//+---------------------------------------------------
//| 求两个时间的天数差 日期格式为 YYYY-MM-dd
//+---------------------------------------------------
function daysBetween(DateOne,DateTwo)
{
var OneMonth = DateOne.substring(5,DateOne.lastIndexOf ('-'));
var OneDay = DateOne.substring(DateOne.length,DateOne.lastIndexOf ('-')+1);
var OneYear = DateOne.substring(0,DateOne.indexOf ('-'));

var TwoMonth = DateTwo.substring(5,DateTwo.lastIndexOf ('-'));
var TwoDay = DateTwo.substring(DateTwo.length,DateTwo.lastIndexOf ('-')+1);
var TwoYear = DateTwo.substring(0,DateTwo.indexOf ('-'));

var cha=((Date.parse(OneMonth+'/'+OneDay+'/'+OneYear)- Date.parse(TwoMonth+'/'+TwoDay+'/'+TwoYear))/86400000);
return Math.abs(cha);
}

//+---------------------------------------------------
//| 日期计算
//+---------------------------------------------------
Date.prototype.DateAdd = function(strInterval, Number) {
var dtTmp = this;
switch (strInterval) {
case 's' :return new Date(Date.parse(dtTmp) + (1000 * Number));
case 'n' :return new Date(Date.parse(dtTmp) + (60000 * Number));
case 'h' :return new Date(Date.parse(dtTmp) + (3600000 * Number));
case 'd' :return new Date(Date.parse(dtTmp) + (86400000 * Number));
case 'w' :return new Date(Date.parse(dtTmp) + ((86400000 * 7) * Number));
case 'q' :return new Date(dtTmp.getFullYear(), (dtTmp.getMonth()) + Number*3, dtTmp.getDate(), dtTmp.getHours(), dtTmp.getMinutes(), dtTmp.getSeconds());
case 'm' :return new Date(dtTmp.getFullYear(), (dtTmp.getMonth()) + Number, dtTmp.getDate(), dtTmp.getHours(), dtTmp.getMinutes(), dtTmp.getSeconds());
case 'y' :return new Date((dtTmp.getFullYear() + Number), dtTmp.getMonth(), dtTmp.getDate(), dtTmp.getHours(), dtTmp.getMinutes(), dtTmp.getSeconds());
}
}

//+---------------------------------------------------
//| 比较日期差 dtEnd 格式为日期型或者 有效日期格式字符串
//+---------------------------------------------------
Date.prototype.DateDiff = function(strInterval, dtEnd) {
var dtStart = this;
if (typeof dtEnd == 'string' )//如果是字符串转换为日期型
{
dtEnd = StringToDate(dtEnd);
}
switch (strInterval) {
case 's' :return parseInt((dtEnd - dtStart) / 1000);
case 'n' :return parseInt((dtEnd - dtStart) / 60000);
case 'h' :return parseInt((dtEnd - dtStart) / 3600000);
case 'd' :return parseInt((dtEnd - dtStart) / 86400000);
case 'w' :return parseInt((dtEnd - dtStart) / (86400000 * 7));
case 'm' :return (dtEnd.getMonth()+1)+((dtEnd.getFullYear()-dtStart.getFullYear())*12) - (dtStart.getMonth()+1);
case 'y' :return dtEnd.getFullYear() - dtStart.getFullYear();
}
}

//+---------------------------------------------------
//| 日期输出字符串，重载了系统的toString方法
//+---------------------------------------------------
Date.prototype.toString = function(showWeek)
{
var myDate= this;
var str = myDate.toLocaleDateString();
if (showWeek)
{
var Week = ['日','一','二','三','四','五','六'];
str += ' 星期' + Week[myDate.getDay()];
}
return str;
}

//+---------------------------------------------------
//| 日期合法性验证
//| 格式为：YYYY-MM-DD或YYYY/MM/DD
//+---------------------------------------------------
function IsValidDate(DateStr)
{
var sDate=DateStr.replace(/(^\s+|\s+$)/g,''); //去两边空格;
if(sDate=='') return true;
//如果格式满足YYYY-(/)MM-(/)DD或YYYY-(/)M-(/)DD或YYYY-(/)M-(/)D或YYYY-(/)MM-(/)D就替换为''
//数据库中，合法日期可以是:YYYY-MM/DD(2003-3/21),数据库会自动转换为YYYY-MM-DD格式
var s = sDate.replace(/[\d]{ 4,4 }[\-/]{ 1 }[\d]{ 1,2 }[\-/]{ 1 }[\d]{ 1,2 }/g,'');
if (s=='') //说明格式满足YYYY-MM-DD或YYYY-M-DD或YYYY-M-D或YYYY-MM-D
{
var t=new Date(sDate.replace(/\-/g,'/'));
var ar = sDate.split(/[-/:]/);
if(ar[0] != t.getYear() || ar[1] != t.getMonth()+1 || ar[2] != t.getDate())
{
//alert('错误的日期格式！格式为：YYYY-MM-DD或YYYY/MM/DD。注意闰年。');
return false;
}
}
else
{
//alert('错误的日期格式！格式为：YYYY-MM-DD或YYYY/MM/DD。注意闰年。');
return false;
}
return true;
}

//+---------------------------------------------------
//| 日期时间检查
//| 格式为：YYYY-MM-DD HH:MM:SS
//+---------------------------------------------------
function CheckDateTime(str)
{
var reg = /^(\d+)-(\d{ 1,2 })-(\d{ 1,2 }) (\d{ 1,2 }):(\d{ 1,2 }):(\d{ 1,2 })$/;
var r = str.match(reg);
if(r==null)return false;
r[2]=r[2]-1;
var d= new Date(r[1],r[2],r[3],r[4],r[5],r[6]);
if(d.getFullYear()!=r[1])return false;
if(d.getMonth()!=r[2])return false;
if(d.getDate()!=r[3])return false;
if(d.getHours()!=r[4])return false;
if(d.getMinutes()!=r[5])return false;
if(d.getSeconds()!=r[6])return false;
return true;
}

//+---------------------------------------------------
//| 把日期分割成数组
//+---------------------------------------------------
Date.prototype.toArray = function()
{
var myDate = this;
var myArray = Array();
myArray[0] = myDate.getFullYear();
myArray[1] = myDate.getMonth();
myArray[2] = myDate.getDate();
myArray[3] = myDate.getHours();
myArray[4] = myDate.getMinutes();
myArray[5] = myDate.getSeconds();
return myArray;
}

//+---------------------------------------------------
//| 取得日期数据信息
//| 参数 interval 表示数据类型
//| y 年 m月 d日 w星期 ww周 h时 n分 s秒
//+---------------------------------------------------
Date.prototype.DatePart = function(interval)
{
var myDate = this;
var partStr='';
var Week = ['日','一','二','三','四','五','六'];
switch (interval)
{
case 'y' :partStr = myDate.getFullYear();break;
case 'm' :partStr = myDate.getMonth()+1;break;
case 'd' :partStr = myDate.getDate();break;
case 'w' :partStr = Week[myDate.getDay()];break;
case 'ww' :partStr = myDate.WeekNumOfYear();break;
case 'h' :partStr = myDate.getHours();break;
case 'n' :partStr = myDate.getMinutes();break;
case 's' :partStr = myDate.getSeconds();break;
}
return partStr;
}

//+---------------------------------------------------
//| 取得当前日期所在月的最大天数
//+---------------------------------------------------
Date.prototype.MaxDayOfDate = function()
{
var myDate = this;
var ary = myDate.toArray();
var date1 = (new Date(ary[0],ary[1]+1,1));
var date2 = date1.dateAdd(1,'m',1);
var result = dateDiff(date1.Format('yyyy-MM-dd'),date2.Format('yyyy-MM-dd'));
return result;
}

//+---------------------------------------------------
//| 取得当前日期所在周是一年中的第几周
//+---------------------------------------------------
Date.prototype.WeekNumOfYear = function()
{
var myDate = this;
var ary = myDate.toArray();
var year = ary[0];
var month = ary[1]+1;
var day = ary[2];
document.write('< script language=VBScript\> \n');
document.write('myDate = DateValue(''+month+'-'+day+'-'+year+'') \n');
document.write('result = DatePart('ww', myDate) \n');
document.write(' \n');
return result;
}

//+---------------------------------------------------
//| 字符串转成日期类型
//| 格式 MM/dd/YYYY MM-dd-YYYY YYYY/MM/dd YYYY-MM-dd
//+---------------------------------------------------
function StringToDate(DateStr)
{

var converted = Date.parse(DateStr);
var myDate = new Date(converted);
if (isNaN(myDate))
{
//var delimCahar = DateStr.indexOf('/')!=-1?'/':'-';
var arys= DateStr.split('-');
myDate = new Date(arys[0],--arys[1],arys[2]);
}
return myDate;
}