我在这里看到了一个可能的答案，但那是YYYY-MM-DD：JavaScript date validation
我为MM-DD-YYYY修改了上面的代码，但我仍然无法让它工作：
String.prototype.isValidDate = function()
{
var IsoDateRe = new RegExp("^([0-9]{2})-([0-9]{2})-([0-9]{4})$");
var matches = IsoDateRe.exec(this);
if (!matches) return false;
var composedDate = new Date(matches[3], (matches[1] - 1), matches[2]);
return ((composedDate.getMonth() == (matches[1] - 1)) &&
(composedDate.getDate() == matches[2]) &&
(composedDate.getFullYear() == matches[3]));
}
如何让上述代码适用于MM-DD-YYYY，更好的是MM / DD / YYYY？
感谢。
答案 0 :(得分：77)
function isValidDate(date)
{
var matches = /^(\d{1,2})[-\/](\d{1,2})[-\/](\d{4})$/.exec(date);
if (matches == null) return false;
var d = matches[2];
var m = matches[1] - 1;
var y = matches[3];
var composedDate = new Date(y, m, d);
return composedDate.getDate() == d &&
composedDate.getMonth() == m &&
composedDate.getFullYear() == y;
}
console.log(isValidDate('10-12-1961'));
console.log(isValidDate('12/11/1961'));
console.log(isValidDate('02-11-1961'));
console.log(isValidDate('12/01/1961'));
console.log(isValidDate('13-11-1961'));
console.log(isValidDate('11-31-1961'));
console.log(isValidDate('11-31-1061'));
有效。 （使用Firebug测试，因此使用console.log（）。）
答案 1 :(得分：12)
function isValidDate(date) {
var valid = true;
date = date.replace('/-/g', '');
var month = parseInt(date.substring(0, 2),10);
var day = parseInt(date.substring(2, 4),10);
var year = parseInt(date.substring(4, 8),10);
if(isNaN(month) || isNaN(day) || isNaN(year)) return false;
if((month < 1) || (month > 12)) valid = false;
else if((day < 1) || (day > 31)) valid = false;
else if(((month == 4) || (month == 6) || (month == 9) || (month == 11)) && (day > 30)) valid = false;
else if((month == 2) && (((year % 400) == 0) || ((year % 4) == 0)) && ((year % 100) != 0) && (day > 29)) valid = false;
else if((month == 2) && ((year % 100) == 0) && (day > 29)) valid = false;
else if((month == 2) && (day > 28)) valid = false;
return valid;
}
这将检查每个月的有效日期和有效的闰年。
答案 2 :(得分：5)
如何以“任何”日期格式验证日期？我一直在使用DateJS库并将其添加到现有表单中，以确保我获得有效的日期和时间。时间格式化我想要的方式。用户甚至可以输入“现在”和“明天”等内容，并将其转换为有效日期。
这是dateJS库： http://www.datejs.com/
这是我写的jQuery提示： http://www.ssmedia.com/utilities/jquery/index.cfm/datejs.htm
答案 3 :(得分：4)
我会使用Moment.js来执行此任务。它使非常容易解析日期，并且还支持以正确的格式检测无效日期 1 。例如，考虑this example：
var formats = ['MM-DD-YYYY', 'MM/DD/YYYY']
moment('11/28/1981', formats).isValid() // true
moment('2-29-2003', formats).isValid() // false (not leap year)
moment('2-29-2004', formats).isValid() // true (leap year)
首先moment(.., formats)用于根据提供的本地化格式解析输入。然后在生成的时刻对象上调用isValid函数，以便我们可以实际判断它是否是有效的日期。
这可以用来简单地派生出isValidDate方法：
String.prototype.isValidDate = function() {
var formats = ['MM-DD-YYYY', 'MM/DD/YYYY'];
return moment("" + this, formats).isValid();
}
1 由于我可以找到关于这个问题的稀少的评论，我只会使用moment.js来涵盖Gregorian calendar所涵盖的日期。可能有其他（包括历史或科学）日历的插件。
答案 4 :(得分：3)
我使用此正则表达式来验证MM-DD-YYYY：
function isValidDate(subject){
if (subject.match(/^(?:(0[1-9]|1[012])[\- \/.](0[1-9]|[12][0-9]|3[01])[\- \/.](19|20)[0-9]{2})$/)){
return true;
}else{
return false;
}
}
它只匹配有效月份，您可以使用/ - 或。作为分隔符。
答案 5 :(得分：2)
什么不起作用？这是经过测试的版本：
String.prototype.isValidDate = function() {
var match = this.match(/^([0-9]{2})\/([0-9]{2})\/([0-9]{4})$/);
var test = new Date(match[3], match[1] - 1, match[2]);
return (
(test.getMonth() == match[1] - 1) &&
(test.getDate() == match[2]) &&
(test.getFullYear() == match[3])
);
}
var date = '12/08/1984'; // Date() is 'Sat Dec 08 1984 00:00:00 GMT-0800 (PST)'
alert(date.isValidDate() ); // true
答案 6 :(得分：2)
此功能将验证日期，以确定日期是否正确，或者格式是否正确：DD / MM / YYYY。
function isValidDate(date)
{
var matches = /^(\d{2})[-\/](\d{2})[-\/](\d{4})$/.exec(date);
if (matches == null) return false;
var d = matches[1];
var m = matches[2]-1;
var y = matches[3];
var composedDate = new Date(y, m, d);
return composedDate.getDate() == d &&
composedDate.getMonth() == m &&
composedDate.getFullYear() == y;
}
console.log(isValidDate('10-12-1961'));
console.log(isValidDate('12/11/1961'));
console.log(isValidDate('02-11-1961'));
console.log(isValidDate('12/01/1961'));
console.log(isValidDate('13-11-1961'));
console.log(isValidDate('11-31-1961'));
console.log(isValidDate('11-31-1061'));
答案 7 :(得分：1)
简单的解决方法
var day = document.getElementById("DayTextBox").value;
var regExp = /^([1-9]|[1][012])\/|-([1-9]|[1][0-9]|[2][0-9]|[3][01])\/|-([1][6-9][0-9][0-9]|[2][0][01][0-9])$/;
return regExp.test(day);
答案 8 :(得分：1)
您可以通过将函数的前两行更改为此来简化它：
var matches = this.match(/^([0-9]{2})\/([0-9]{2})\/([0-9]{4})$/);
或者，只需将参数更改为RegExp构造函数即
^([0-9]{2})\/([0-9]{2})\/([0-9]{4})$
答案 9 :(得分：0)
这是用于验证formate中的日期字符串dd.mm.yyyy很容易定制它。你只需要在isValidDate（）中调整pos1和pos2。
var dtCh =“。”; var minYear = 1900;
function isInteger(s){
var i;
for (i = 0; i < s.length; i++){
// Check that current character is number.
var c = s.charAt(i);
if (((c < "0") || (c > "9"))) return false;
}
// All characters are numbers.
return true;
}
function stripCharsInBag(s, bag){
var i;
var returnString = "";
// Search through string's characters one by one.
// If character is not in bag, append to returnString.
for (i = 0; i < s.length; i++){
var c = s.charAt(i);
if (bag.indexOf(c) == -1) returnString += c;
}
return returnString;
}
function daysInFebruary (year){
// February has 29 days in any year evenly divisible by four,
// EXCEPT for centurial years which are not also divisible by 400.
return (((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0))) ? 29 : 28 );
}
function DaysArray(n) {
for (var i = 1; i <= n; i++) {
this[i] = 31;
if (i==4 || i==6 || i==9 || i==11) {
this[i] = 30;
}
if (i==2) {
this[i] = 29;
}
}
return this;
}
function isValidDate(dtStr){
var daysInMonth = DaysArray(12);
var pos1=dtStr.indexOf(dtCh);
var pos2=dtStr.indexOf(dtCh,pos1+1);
var strDay=dtStr.substring(0,pos1);
var strMonth=dtStr.substring(pos1+1,pos2);
var strYear=dtStr.substring(pos2+1);
strYr=strYear;
if (strDay.charAt(0)=="0" && strDay.length>1)
strDay=strDay.substring(1);
if (strMonth.charAt(0)=="0" && strMonth.length>1)
strMonth=strMonth.substring(1);
for (var i = 1; i <= 3; i++) {
if (strYr.charAt(0)=="0" && strYr.length>1)
strYr=strYr.substring(1);
}
month=parseInt(strMonth);
day=parseInt(strDay);
year=parseInt(strYr);
if (pos1==-1 || pos2==-1){
alert("The date format should be : dd.mm.yyyy");
return false;
}
if (strMonth.length<1 || month<1 || month>12){
alert("Please enter a valid month");
return false;
}
if (strDay.length<1 || day<1 || day>31 || (month==2 && day>daysInFebruary(year)) || day > daysInMonth[month]){
alert("Please enter a valid day");
return false;
}
if (strYear.length != 4 || year==0 || year<minYear){
alert("Please enter a valid 4 digit year after "+minYear);
return false;
}
if (dtStr.indexOf(dtCh,pos2+1)!=-1 || isInteger(stripCharsInBag(dtStr, dtCh))==false){
alert("Please enter a valid date");
return false;
}
return true;
}
答案 10 :(得分：0)
将此函数传递给日期，格式为// 10-10-2012，id为object。
function isValidDateFormat(date, id)
{
var todayDate = new Date();
var matches = /^(\d{2})[-\/](\d{2})[-\/](\d{4})$/.exec(date);
if (matches == null)
{
if(date != '__-__-____')
{
alert('Please enter valid date');
}
}
else
{
var day = 31;
var month = 12;
var b_date = date.split("-");
if(b_date[0] <= day)
{
if(b_date[1] <= month)
{
if(b_date[2] >= 1900 && b_date[2] <= todayDate.getFullYear())
{
return true;
}
else
{
$("#"+id).val('');
alert('Please enter valid Year');
}
}
else
{
$("#"+id).val('');
alert('Please enter valid Month');
}
}
else
{
alert('Please enter valid Day');
$("#"+id).val('');
}
}
}
答案 11 :(得分：0)
if (document.getElementById('expiryDay').value != test(match("/^([0-9]{2})\/([0-9]{2})$/"))){
alert("Enter the date in two digit month flowed by two digits year \n");
}
答案 12 :(得分：0)
<!DOCTYPE html>
<html>
<head>
<title></title>
<script>
function dateCheck(inputText) {
debugger;
var dateFormat = /^(0?[1-9]|[12][0-9]|3[01])[\/\-](0?[1-9]|1[012])[\/\-]\d{4}$/;
var flag = 1;
if (inputText.value.match(dateFormat)) {
document.myForm.dateInput.focus();
var inputFormat1 = inputText.value.split('/');
var inputFormat2 = inputText.value.split('-');
linputFormat1 = inputFormat1.length;
linputFormat2 = inputFormat2.length;
if (linputFormat1 > 1) {
var pdate = inputText.value.split('/');
}
else if (linputFormat2 > 1) {
var pdate = inputText.value.split('-');
}
var date = parseInt(pdate[0]);
var month = parseInt(pdate[1]);
var year = parseInt(pdate[2]);
var ListofDays = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31];
if (month == 1 || month > 2) {
if (date > ListofDays[month - 1]) {
alert("Invalid date format!");
return false;
}
}
if (month == 2) {
var leapYear = false;
if ((!(year % 4) && year % 100) || !(year % 400)) {
leapYear = true;
}
if ((leapYear == false) && (date >= 29)) {
alert("Invalid date format!");
return false;
}
if ((leapYear == true) && (date > 29)) {
alert("Invalid date format!");
return false;
}
}
if (flag == 1) {
alert("Valid Date");
}
}
else {
alert("Invalid date format!");
document.myForm.dateInput.focus();
return false;
}
}
function restrictCharacters(evt) {
evt = (evt) ? evt : window.event;
var charCode = (evt.which) ? evt.which : evt.keyCode;
if (((charCode >= '48') && (charCode <= '57')) || (charCode == '47')) {
return true;
}
else {
return false;
}
}
</script>
</head>
<body>
<div>
<form name="myForm" action="#">
<table>
<tr>
<td>Enter Date</td>
<td><input type="text" onkeypress="return restrictCharacters(event);" name="dateInput"/></td>
<td></td>
<td><span id="span2"></span></td>
</tr>
<tr>
<td></td>
<td><input type="button" name="submit" value="Submit" onclick="dateCheck(document.myForm.dateInput)" /></td>
</tr>
</table>
</form>
</div>
</body>
</html>
答案 13 :(得分：0)
请在下面的代码中找到，该代码可以对任何提供的格式执行日期验证，或者根据用户区域设置来验证开始日期和结束日期。可能有一些更好的方法，但已经提出了这个。已经测试过以下格式：MM / dd / yyyy，dd / MM / yyyy，yyyy-MM-dd，yyyy.MM.dd，yyyy / MM / dd和dd-MM-yyyy。
注意提供的日期格式和日期字符串齐头并进。
<script type="text/javascript">
function validate(format) {
if(isAfterCurrentDate(document.getElementById('start').value, format)) {
alert('Date is after the current date.');
} else {
alert('Date is not after the current date.');
}
if(isBeforeCurrentDate(document.getElementById('start').value, format)) {
alert('Date is before current date.');
} else {
alert('Date is not before current date.');
}
if(isCurrentDate(document.getElementById('start').value, format)) {
alert('Date is current date.');
} else {
alert('Date is not a current date.');
}
if (isBefore(document.getElementById('start').value, document.getElementById('end').value, format)) {
alert('Start/Effective Date cannot be greater than End/Expiration Date');
} else {
alert('Valid dates...');
}
if (isAfter(document.getElementById('start').value, document.getElementById('end').value, format)) {
alert('End/Expiration Date cannot be less than Start/Effective Date');
} else {
alert('Valid dates...');
}
if (isEquals(document.getElementById('start').value, document.getElementById('end').value, format)) {
alert('Dates are equals...');
} else {
alert('Dates are not equals...');
}
if (isDate(document.getElementById('start').value, format)) {
alert('Is valid date...');
} else {
alert('Is invalid date...');
}
}
/**
* This method gets the year index from the supplied format
*/
function getYearIndex(format) {
var tokens = splitDateFormat(format);
if (tokens[0] === 'YYYY'
|| tokens[0] === 'yyyy') {
return 0;
} else if (tokens[1]=== 'YYYY'
|| tokens[1] === 'yyyy') {
return 1;
} else if (tokens[2] === 'YYYY'
|| tokens[2] === 'yyyy') {
return 2;
}
// Returning the default value as -1
return -1;
}
/**
* This method returns the year string located at the supplied index
*/
function getYear(date, index) {
var tokens = splitDateFormat(date);
return tokens[index];
}
/**
* This method gets the month index from the supplied format
*/
function getMonthIndex(format) {
var tokens = splitDateFormat(format);
if (tokens[0] === 'MM'
|| tokens[0] === 'mm') {
return 0;
} else if (tokens[1] === 'MM'
|| tokens[1] === 'mm') {
return 1;
} else if (tokens[2] === 'MM'
|| tokens[2] === 'mm') {
return 2;
}
// Returning the default value as -1
return -1;
}
/**
* This method returns the month string located at the supplied index
*/
function getMonth(date, index) {
var tokens = splitDateFormat(date);
return tokens[index];
}
/**
* This method gets the date index from the supplied format
*/
function getDateIndex(format) {
var tokens = splitDateFormat(format);
if (tokens[0] === 'DD'
|| tokens[0] === 'dd') {
return 0;
} else if (tokens[1] === 'DD'
|| tokens[1] === 'dd') {
return 1;
} else if (tokens[2] === 'DD'
|| tokens[2] === 'dd') {
return 2;
}
// Returning the default value as -1
return -1;
}
/**
* This method returns the date string located at the supplied index
*/
function getDate(date, index) {
var tokens = splitDateFormat(date);
return tokens[index];
}
/**
* This method returns true if date1 is before date2 else return false
*/
function isBefore(date1, date2, format) {
// Validating if date1 date is greater than the date2 date
if (new Date(getYear(date1, getYearIndex(format)),
getMonth(date1, getMonthIndex(format)) - 1,
getDate(date1, getDateIndex(format))).getTime()
> new Date(getYear(date2, getYearIndex(format)),
getMonth(date2, getMonthIndex(format)) - 1,
getDate(date2, getDateIndex(format))).getTime()) {
return true;
}
return false;
}
/**
* This method returns true if date1 is after date2 else return false
*/
function isAfter(date1, date2, format) {
// Validating if date2 date is less than the date1 date
if (new Date(getYear(date2, getYearIndex(format)),
getMonth(date2, getMonthIndex(format)) - 1,
getDate(date2, getDateIndex(format))).getTime()
< new Date(getYear(date1, getYearIndex(format)),
getMonth(date1, getMonthIndex(format)) - 1,
getDate(date1, getDateIndex(format))).getTime()
) {
return true;
}
return false;
}
/**
* This method returns true if date1 is equals to date2 else return false
*/
function isEquals(date1, date2, format) {
// Validating if date1 date is equals to the date2 date
if (new Date(getYear(date1, getYearIndex(format)),
getMonth(date1, getMonthIndex(format)) - 1,
getDate(date1, getDateIndex(format))).getTime()
=== new Date(getYear(date2, getYearIndex(format)),
getMonth(date2, getMonthIndex(format)) - 1,
getDate(date2, getDateIndex(format))).getTime()) {
return true;
}
return false;
}
/**
* This method validates and returns true if the supplied date is
* equals to the current date.
*/
function isCurrentDate(date, format) {
// Validating if the supplied date is the current date
if (new Date(getYear(date, getYearIndex(format)),
getMonth(date, getMonthIndex(format)) - 1,
getDate(date, getDateIndex(format))).getTime()
=== new Date(new Date().getFullYear(),
new Date().getMonth(),
new Date().getDate()).getTime()) {
return true;
}
return false;
}
/**
* This method validates and returns true if the supplied date value
* is before the current date.
*/
function isBeforeCurrentDate(date, format) {
// Validating if the supplied date is before the current date
if (new Date(getYear(date, getYearIndex(format)),
getMonth(date, getMonthIndex(format)) - 1,
getDate(date, getDateIndex(format))).getTime()
< new Date(new Date().getFullYear(),
new Date().getMonth(),
new Date().getDate()).getTime()) {
return true;
}
return false;
}
/**
* This method validates and returns true if the supplied date value
* is after the current date.
*/
function isAfterCurrentDate(date, format) {
// Validating if the supplied date is before the current date
if (new Date(getYear(date, getYearIndex(format)),
getMonth(date, getMonthIndex(format)) - 1,
getDate(date, getDateIndex(format))).getTime()
> new Date(new Date().getFullYear(),
new Date().getMonth(),
new Date().getDate()).getTime()) {
return true;
}
return false;
}
/**
* This method splits the supplied date OR format based
* on non alpha numeric characters in the supplied string.
*/
function splitDateFormat(dateFormat) {
// Spliting the supplied string based on non characters
return dateFormat.split(/\W/);
}
/*
* This method validates if the supplied value is a valid date.
*/
function isDate(date, format) {
// Validating if the supplied date string is valid and not a NaN (Not a Number)
if (!isNaN(new Date(getYear(date, getYearIndex(format)),
getMonth(date, getMonthIndex(format)) - 1,
getDate(date, getDateIndex(format))))) {
return true;
}
return false;
}
以下是HTML代码段
<input type="text" name="start" id="start" size="10" value="05/31/2016" />
<br/>
<input type="text" name="end" id="end" size="10" value="04/28/2016" />
<br/>
<input type="button" value="Submit" onclick="javascript:validate('MM/dd/yyyy');" />
答案 14 :(得分：0)
如果您的日期需要与DD.MM.YYYY匹配并使用AngularJS，请使用以下代码：
$scope.validDate = function(value){
var matches = /^(\d{1,2})[.](\d{1,2})[.](\d{4})$/.exec(value);
if (matches == null) return false;
var d = matches[1];
var m = matches[2] - 1;
var y = matches[3];
var composedDate = new Date(y, m, d);
return composedDate.getDate() == d &&
composedDate.getMonth() == m &&
composedDate.getFullYear() == y;
};
console.log($scope.validDate('22.04.2001'));
console.log($scope.validDate('03.10.2001'));
console.log($scope.validDate('30.02.2001'));
console.log($scope.validDate('23.09.2016'));
console.log($scope.validDate('29.02.2016'));
console.log($scope.validDate('31.02.2016'));
可以找到有关范围对象的更多信息here。如果没有AngularJS，只需将第一行更改为：
ValidDate = new function(value) {
并使用以下方式调用它：
var MyDate= ValidDate('29.09.2016');
答案 15 :(得分：0)
DateFormat = DD.MM.YYYY或D.M.YYYY
function dateValidate(val){
var dateStr = val.split('.');
var date = new Date(dateStr[2], dateStr[1]-1, dateStr[0]);
if(date.getDate() == dateStr[0] && date.getMonth()+1 == dateStr[1] && date.getFullYear() == dateStr[2])
{ return date; }
else{ return 'NotValid';}
}
答案 16 :(得分：0)
试试这个：
function validateDate(dates){
re = /^(\d{1,2})\/(\d{1,2})\/(\d{4})$/;
var days=new Array(31,28,31,30,31,30,31,31,30,31,30,31);
if(regs = dates.match(re)) {
// day value between 1 and 31
if(regs[1] < 1 || regs[1] > 31) {
return false;
}
// month value between 1 and 12
if(regs[2] < 1 || regs[2] > 12) {
return false;
}
var maxday=days[regs[2]-1];
if(regs[2]==2){
if(regs[3]%4==0){
maxday=maxday+1;
}
}
if(regs[1]>maxday){
return false;
}
return true;
}else{
return false;
}
}
答案 17 :(得分：0)
又快又快。
function dateValid(date) {
var match = date.match(/^(\d\d)-(\d\d)-(\d{4})$/) || [];
var m = (match[1] | 0) - 1;
var d = match[2] | 0;
var y = match[3] | 0;
return !(
m < 0 || // Before January
m > 11 || // After December
d < 1 || // Before the 1st of the month
d - 30 > (2741 >> m & 1) || // After the 30th or 31st of the month using bitmap
m == 1 && d - 28 > // After the 28th or 29th of February depending on leap year
(!(y % 4) && y % 100 || !(y % 400)));
}
console.log('02-29-2000', dateValid('02-29-2000'));
console.log('02-29-2001', dateValid('02-29-2001'));
console.log('12-31-1970', dateValid('12-31-1970'));
console.log('Hello', dateValid('Hello'));
答案 18 :(得分：0)
德语变体，但可以改编为Iso
/path?example=test答案 19 :(得分：0)
@Adam Leggett在上面的“快速和快速”上进行了扩展，例如“ 02/30/2020”之类的情况在应为true时返回false。我确实挖了位图...
对于MM / DD / YYYY日期格式验证：
const dateValid = (date) => {
const isLeapYear = (yearNum) => {
return ((yearNum % 100 === 0) ? (yearNum % 400 === 0) : (yearNum % 4 === 0))?
1:
0;
}
const match = date.match(/^(\d\d)\/(\d\d)\/(\d{4})$/) || [];
const month = (match[1] | 0) - 1;
const day = match[2] | 0;
const year = match[3] | 0;
const dateEval=!( month < 0 || // Before January
month > 11 || // After December
day < 1 || // Before the 1st of the month
day - 30 > (2773 >> month & 1) ||
month === 1 && day - 28 > isLeapYear(year)
// Day is 28 or 29, month is 02, year is leap year ==> true
);
return `\nDate: ${date}\n\n
Valid Date?: ${dateEval}\n
=======================================`
}
console.log(dateValid('02/28/2020')) // true
console.log(dateValid('02/29/2020')) // true
console.log(dateValid('02/30/2020')) // false
console.log(dateValid('01/31/2020')) // true
console.log(dateValid('01/31/2000')) // true
console.log(dateValid('04/31/2020')) // false
console.log(dateValid('04/31/2000')) // false
console.log(dateValid('04/30/2020')) // true
console.log(dateValid('01/32/2020')) // false
console.log(dateValid('02/28/2021')) // true
console.log(dateValid('02/29/2021')) // false
console.log(dateValid('02/30/2021')) // false
console.log(dateValid('02/28/2000')) // true
console.log(dateValid('02/29/2000')) // true
console.log(dateValid('02/30/2000')) // false
console.log(dateValid('02/28/2001')) // true
console.log(dateValid('02/29/2001')) // false
console.log(dateValid('02/30/2001')) // false
对于MM-DD-YYYY日期格式验证：将\/的模式中的match替换为-。
答案 20 :(得分：-2)
<script language = "Javascript">
// Declaring valid date character, minimum year and maximum year
var dtCh= "/";
var minYear=1900;
var maxYear=2100;
function isInteger(s){
var i;
for (i = 0; i < s.length; i++){
// Check that current character is number.
var c = s.charAt(i);
if (((c < "0") || (c > "9"))) return false;
}
// All characters are numbers.
return true;
}
function stripCharsInBag(s, bag){
var i;
var returnString = "";
// Search through string's characters one by one.
// If character is not in bag, append to returnString.
for (i = 0; i < s.length; i++){
var c = s.charAt(i);
if (bag.indexOf(c) == -1) returnString += c;
}
return returnString;
}
function daysInFebruary (year){
// February has 29 days in any year evenly divisible by four,
// EXCEPT for centurial years which are not also divisible by 400.
return (((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0))) ? 29 : 28 );
}
function DaysArray(n) {
for (var i = 1; i <= n; i++) {
this[i] = 31
if (i==4 || i==6 || i==9 || i==11) {this[i] = 30}
if (i==2) {this[i] = 29}
}
return this
}
function isDate(dtStr){
var daysInMonth = DaysArray(12)
var pos1=dtStr.indexOf(dtCh)
var pos2=dtStr.indexOf(dtCh,pos1+1)
var strDay=dtStr.substring(0,pos1)
var strMonth=dtStr.substring(pos1+1,pos2)
var strYear=dtStr.substring(pos2+1)
strYr=strYear
if (strDay.charAt(0)=="0" && strDay.length>1) strDay=strDay.substring(1)
if (strMonth.charAt(0)=="0" && strMonth.length>1) strMonth=strMonth.substring(1)
for (var i = 1; i <= 3; i++) {
if (strYr.charAt(0)=="0" && strYr.length>1) strYr=strYr.substring(1)
}
month=parseInt(strMonth)
day=parseInt(strDay)
year=parseInt(strYr)
if (pos1==-1 || pos2==-1){
alert("The date format should be : dd/mm/yyyy")
return false
}
if (strMonth.length<1 || month<1 || month>12){
alert("Please enter a valid month")
return false
}
if (strDay.length<1 || day<1 || day>31 || (month==2 && day>daysInFebruary(year)) || day > daysInMonth[month]){
alert("Please enter a valid day")
return false
}
if (strYear.length != 4 || year==0 || year<minYear || year>maxYear){
alert("Please enter a valid 4 digit year between "+minYear+" and "+maxYear)
return false
}
if (dtStr.indexOf(dtCh,pos2+1)!=-1 || isInteger(stripCharsInBag(dtStr, dtCh))==false){
alert("Please enter a valid date")
return false
}
return true
}
function ValidateForm(){
var dt=document.frmSample.txtDateenter code here
if (isDate(dt.value)==false){
dt.focus()
return false
}
return true
}
</script>