20 KiB
date-and-time
This library is a minimalist collection of functions for manipulating JS date and time. It's tiny, simple, easy to learn.
Why
JS modules nowadays are getting more huge and complex, and there are also many dependencies. Trying to keep each module simple and small is meaningful.
Features
- Minimalist. Less than 2k. (minified and gzipped)
- Extensible. Plugin system support.
- Multi language support.
- Universal / Isomorphic. Wherever JS runtime works.
- Older browser support. Even works on IE6. :)
Install
- via npm:
npm install date-and-time --save
- local:
<script src="/path/to/date-and-time.min.js"></script>
Recent Changes
-
0.12.0
- The parser now supports
Z
token to parse timezone offset. - (Breaking Change) Excleded
YY
token from the parser, added it astwo-digit-year
plugin. - (Breaking Change) Decided to change the default behavior of
A
token to fix the non-intuitive definition. Sepcifically, in theformat()
it now outputsAM
/PM
instead ofa.m.
/p.m.
, and in theparse()
it recognizesAM
/PM
only. OtherA
tokens are supported asmeridiem
plugin.token new meaning example default A meridiem (uppercase) AM, PM ✔️ AA meridiem (uppercase with ellipsis) A.M., P.M. a meridiem (lowercase) am, pm aa meridiem (lowercase with ellipsis) a.m., p.m.
- The parser now supports
-
0.11.0
- Added compile() function that precompiling a date-time string for the parser. If you need to process many date-time string with one format, you could get results faster than before by precompiling the format string with this function.
// We have passed a string format at the 2nd parameter each time when calling the parse() function. date.parse('Mar 22 2019 2:54:21 PM', 'MMM D YYYY h:m:s A'); date.parse('Jul 27 2019 4:15:24 AM', 'MMM D YYYY h:m:s A'); date.parse('Dec 25 2019 3:51:11 AM', 'MMM D YYYY h:m:s A'); // You can precompile the string format. const pattern = date.compile('MMM D YYYY h:m:s A'); // The parse() will be able to finish faster than passing the format string each time. date.parse('Mar 22 2019 2:54:21 PM', pattern); date.parse('Jul 27 2019 4:15:24 AM', pattern); date.parse('Dec 25 2019 3:51:11 AM', pattern);
const pattern = date.compile('MMM D YYYY h:m:s A'); // The isValid() will also too. date.isValid('Mar 22 2019 2:54:21 PM', pattern);
-
0.10.0
- (Breaking Change)
YYYY
token now requires 4 digits in theparse()
,preparse()
andisValid()
.
date.parse('31-12-0123', 'DD-MM-YYYY'); // Good date.parse('31-12-123', 'DD-MM-YYYY'); // Not good
- (Breaking Change)
YY
token now requires 2 digits in the same functions.
date.parse('31-12-03', 'DD-MM-YY'); // Good, but it assumes the year is 2003. date.parse('31-12-3', 'DD-MM-YY'); // Not good
- Added
Y
token to support year without zero-padding in the same functions.
date.parse('31-12-123', 'DD-MM-Y'); // Good, 123 AD. date.parse('31-12-3', 'DD-MM-Y'); // Good, 3 AD.
- (Breaking Change)
Usage
- Node.js:
const date = require('date-and-time');
- With a transpiler:
import date from 'date-and-time';
- The browser:
window.date; // global object
API
format(dateObj, formatString[, utc])
- Formatting a date.
- @param {Date} dateObj - a Date object
- @param {string} formatString - a format string
- @param {boolean} [utc] - output as UTC
- @returns {string} a formatted string
const now = new Date();
date.format(now, 'YYYY/MM/DD HH:mm:ss'); // => '2015/01/02 23:14:05'
date.format(now, 'ddd, MMM DD YYYY'); // => 'Fri, Jan 02 2015'
date.format(now, 'hh:mm A [GMT]Z'); // => '11:14 PM GMT-0800'
date.format(now, 'hh:mm A [GMT]Z', true); // => '07:14 AM GMT+0000'
Available tokens and their meanings are as follows:
token | meaning | examples of output |
---|---|---|
YYYY | four-digit year | 0999, 2015 |
YY | two-digit year | 99, 01, 15 |
Y | four-digit year without zero-padding | 2, 44, 888, 2015 |
MMMM | month name (long) | January, December |
MMM | month name (short) | Jan, Dec |
MM | month with zero-padding | 01, 12 |
M | month | 1, 12 |
DD | date with zero-padding | 02, 31 |
D | date | 2, 31 |
dddd | day of week (long) | Friday, Sunday |
ddd | day of week (short) | Fri, Sun |
dd | day of week (very short) | Fr, Su |
HH | 24-hour with zero-padding | 23, 08 |
H | 24-hour | 23, 8 |
hh | 12-hour with zero-padding | 11, 08 |
h | 12-hour | 11, 8 |
A | meridiem (uppercase) | AM, PM |
mm | minute with zero-padding | 14, 07 |
m | minute | 14, 7 |
ss | second with zero-padding | 05, 10 |
s | second | 5, 10 |
SSS | millisecond (high accuracy) | 753, 022 |
SS | millisecond (middle accuracy) | 75, 02 |
S | millisecond (low accuracy) | 7, 0 |
Z | timezone offset | +0100, -0800 |
You could also use the following tokens by importing plugins. See PLUGINS.md for details.
token | meaning | examples of output |
---|---|---|
DDD | ordinal notation of date | 1st, 2nd, 3rd |
AA | meridiem (uppercase with ellipsis) | A.M., P.M. |
a | meridiem (lowercase) | am, pm |
aa | meridiem (lowercase with ellipsis) | a.m., p.m. |
NOTE 1. Comments
String in parenthese [...]
in the formatString
will be ignored as comments:
date.format(new Date(), 'DD-[MM]-YYYY'); // => '02-MM-2015'
date.format(new Date(), '[DD-[MM]-YYYY]'); // => 'DD-[MM]-YYYY'
NOTE 2. Output as UTC
This function usually outputs a local date-time string. Set to true the utc
option (the 3rd parameter) if you would like to get a UTC date-time string.
date.format(new Date(), 'hh:mm A [GMT]Z'); // => '11:14 PM GMT-0800'
date.format(new Date(), 'hh:mm A [GMT]Z', true); // => '07:14 AM GMT+0000'
NOTE 3. More Tokens
You could also define your own tokens. See EXTEND.md for details.
parse(dateString, arg[, utc])
- Parsing a date string.
- @param {string} dateString - a date string
- @param {string|Array.<string>} arg - a format string or a compiled object
- @param {boolean} [utc] - input as UTC
- @returns {Date} a constructed date
date.parse('2015/01/02 23:14:05', 'YYYY/MM/DD HH:mm:ss'); // => Jan 2 2015 23:14:05 GMT-0800
date.parse('02-01-2015', 'DD-MM-YYYY'); // => Jan 2 2015 00:00:00 GMT-0800
date.parse('11:14:05 PM', 'hh:mm:ss A'); // => Jan 1 1970 23:14:05 GMT-0800
date.parse('11:14:05 PM', 'hh:mm:ss A', true); // => Jan 1 1970 23:14:05 GMT+0000 (Jan 1 1970 15:14:05 GMT-0800)
date.parse('23:14:05 GMT+0900', 'HH:mm:ss [GMT]Z'); // => Jan 1 1970 23:14:05 GMT+0900 (Jan 1 1970 06:14:05 GMT-0800)
date.parse('Jam 1 2017', 'MMM D YYYY'); // => Invalid Date
date.parse('Feb 29 2017', 'MMM D YYYY'); // => Invalid Date
Available tokens and their meanings are as follows:
token | meaning | examples of acceptable form |
---|---|---|
YYYY | four-digit year | 0999, 2015 |
Y | four-digit year without zero-padding | 2, 44, 88, 2015 |
MMMM | month name (long) | January, December |
MMM | month name (short) | Jan, Dec |
MM | month with zero-padding | 01, 12 |
M | month | 1, 12 |
DD | date with zero-padding | 02, 31 |
D | date | 2, 31 |
HH | 24-hour with zero-padding | 23, 08 |
H | 24-hour | 23, 8 |
hh | 12-hour with zero-padding | 11, 08 |
h | 12-hour | 11, 8 |
A | meridiem (uppercase) | AM, PM |
mm | minute with zero-padding | 14, 07 |
m | minute | 14, 7 |
ss | second with zero-padding | 05, 10 |
s | second | 5, 10 |
SSS | millisecond (high accuracy) | 753, 022 |
SS | millisecond (middle accuracy) | 75, 02 |
S | millisecond (low accuracy) | 7, 0 |
Z | timezone offset | +0100, -0800 |
You could also use the following tokens by importing plugins. See PLUGINS.md for details.
token | meaning | examples of acceptable form |
---|---|---|
YY | two-digit year | 90, 00, 08, 19 |
Y | two-digit year without zero-padding | 90, 0, 8, 19 |
A | meridiem | AM, PM, A.M., P.M., am, pm, a.m., p.m. |
NOTE 1. Invalid Date
If the function fails to parse, it will return Invalid Date
. Notice that the Invalid Date
is a Date object, not NaN
or null
. You could tell whether the Date object is invalid as follows:
const today = date.parse('Jam 1 2017', 'MMM D YYYY');
if (isNaN(today)) {
// Failure
}
NOTE 2. Input as UTC
This function usually assumes the dateString
is a local date-time. Set to true the utc
option (the 3rd parameter) if it is a UTC date-time.
date.parse('11:14:05 PM', 'hh:mm:ss A'); // => Jan 1 1970 23:14:05 GMT-0800
date.parse('11:14:05 PM', 'hh:mm:ss A', true); // => Jan 1 1970 23:14:05 GMT+0000 (Jan 1 1970 15:14:05 GMT-0800)
NOTE 3. Default Date Time
Default date is January 1, 1970
, time is 00:00:00.000
. Values not passed will be complemented with them:
date.parse('11:14:05 PM', 'hh:mm:ss A'); // => Jan 1 1970 23:14:05 GMT-0800
date.parse('Feb 2000', 'MMM YYYY'); // => Feb 1 2000 00:00:00 GMT-0800
NOTE 4. Max Date / Min Date
Parsable maximum date is December 31, 9999
, minimum date is January 1, 0001
.
date.parse('Dec 31 9999', 'MMM D YYYY'); // => Dec 31 9999 00:00:00 GMT-0800
date.parse('Dec 31 10000', 'MMM D YYYY'); // => Invalid Date
date.parse('Jan 1 0001', 'MMM D YYYY'); // => Jan 1 0001 00:00:00 GMT-0800
date.parse('Jan 1 0000', 'MMM D YYYY'); // => Invalid Date
NOTE 5. 12-hour notation and Meridiem
If use hh
or h
(12-hour) token, use together A
(meridiem) token to get the right value.
date.parse('11:14:05', 'hh:mm:ss'); // => Jan 1 1970 11:14:05 GMT-0800
date.parse('11:14:05 PM', 'hh:mm:ss A'); // => Jan 1 1970 23:14:05 GMT-0800
NOTE 6. Comments
String in parenthese [...]
in the formatString
will be ignored as comments:
date.parse('12 hours 34 minutes', 'HH hours mm minutes'); // => Invalid Date
date.parse('12 hours 34 minutes', 'HH [hours] mm [minutes]'); // => Jan 1 1970 12:34:00 GMT-0800
NOTE 7. Wildcard
A white space works as a wildcard token. This token is not interpret into anything. This means it can be ignored a specific variable string. For example, when you would like to ignore a time part from a date string, you can write as follows:
// This will be an error.
date.parse('2015/01/02 11:14:05', 'YYYY/MM/DD'); // => Invalid Date
// Append the same length white spaces behind the formatString.
date.parse('2015/01/02 11:14:05', 'YYYY/MM/DD '); // => Jan 2 2015 00:00:00 GMT-0800
compile(formatString)
- Compiling a format string for the parser.
- @param {string} formatString - a format string
- @returns {Array.<string>} a compiled object
const pattern = date.compile('MMM D YYYY h:m:s A');
date.parse('Mar 22 2019 2:54:21 PM', pattern);
date.parse('Jul 27 2019 4:15:24 AM', pattern);
date.parse('Dec 25 2019 3:51:11 AM', pattern);
If you are going to call the parse()
or the isValid()
many times with one string format, recommended to precompile and reuse it for performance.
preparse(dateString, arg)
- Pre-parsing a date string.
- @param {string} dateString - a date string
- @param {string|Array.<string>} arg - a format string or a compiled object
- @returns {Object} a date structure
This function takes exactly the same parameters with the parse()
, but returns a date structure as follows unlike that:
date.preparse('Fri Jan 2015 02 23:14:05 GMT-0800', ' MMM YYYY DD HH:mm:ss [GMT]Z');
{
Y: 2015, // Year
M: 1, // Month
D: 2, // Day
H: 23, // 24-hour
A: 0, // Meridiem
h: 0, // 12-hour
m: 14, // Minute
s: 5, // Second
S: 0, // Millisecond
Z: 480, // Timsezone offset
_index: 33, // Pointer offset
_length: 33, // Length of the date string
_match: 7 // Token matching count
}
This date structure provides a parsing result. You would be able to tell from it how the date string was parsed(, or why the parsing was failed).
isValid(arg1[, arg2])
- Validation.
- @param {Object|string} arg1 - a date structure or a date string
- @param {string|Array.<string>} [arg2] - a format string or a compiled object
- @returns {boolean} whether the date string is a valid date
This function takes either exactly the same parameters with the parse()
or a date structure which the preparse()
returns, evaluates the validity of them.
date.isValid('2015/01/02 23:14:05', 'YYYY/MM/DD HH:mm:ss'); // => true
date.isValid('29-02-2015', 'DD-MM-YYYY'); // => false
const result = date.preparse('2015/01/02 23:14:05', 'YYYY/MM/DD HH:mm:ss');
date.isValid(result); // => true
addYears(dateObj, years)
- Adding years.
- @param {Date} dateObj - a Date object
- @param {number} years - number of years to add
- @returns {Date} a date after adding the value
const now = new Date();
const next_year = date.addYears(now, 1);
addMonths(dateObj, months)
- Adding months.
- @param {Date} dateObj - a Date object
- @param {number} months - number of months to add
- @returns {Date} a date after adding the value
const now = new Date();
const next_month = date.addMonths(now, 1);
addDays(dateObj, days)
- Adding days.
- @param {Date} dateObj - a Date object
- @param {number} days - number of days to add
- @returns {Date} a date after adding the value
const now = new Date();
const yesterday = date.addDays(now, -1);
addHours(dateObj, hours)
- Adding hours.
- @param {Date} dateObj - a Date object
- @param {number} hours - number of hours to add
- @returns {Date} a date after adding the value
const now = new Date();
const an_hour_ago = date.addHours(now, -1);
addMinutes(dateObj, minutes)
- Adding minutes.
- @param {Date} dateObj - a Date object
- @param {number} minutes - number of minutes to add
- @returns {Date} a date after adding the value
const now = new Date();
const two_minutes_later = date.addMinutes(now, 2);
addSeconds(dateObj, seconds)
- Adding seconds.
- @param {Date} dateObj - a Date object
- @param {number} seconds - number of seconds to add
- @returns {Date} a date after adding the value
const now = new Date();
const three_seconds_ago = date.addSeconds(now, -3);
addMilliseconds(dateObj, milliseconds)
- Adding milliseconds.
- @param {Date} dateObj - a Date object
- @param {number} milliseconds - number of milliseconds to add
- @returns {Date} a date after adding the value
const now = new Date();
const a_millisecond_later = date.addMilliseconds(now, 1);
subtract(date1, date2)
- Subtracting.
- @param {Date} date1 - a Date object
- @param {Date} date2 - a Date object
- @returns {Object} a result object subtracting date2 from date1
const today = new Date(2015, 0, 2);
const yesterday = new Date(2015, 0, 1);
date.subtract(today, yesterday).toDays(); // => 1 = today - yesterday
date.subtract(today, yesterday).toHours(); // => 24
date.subtract(today, yesterday).toMinutes(); // => 1440
date.subtract(today, yesterday).toSeconds(); // => 86400
date.subtract(today, yesterday).toMilliseconds(); // => 86400000
isLeapYear(y)
- Leap year.
- @param {number} y - year
- @returns {boolean} whether the year is a leap year
date.isLeapYear(2015); // => false
date.isLeapYear(2012); // => true
isSameDay(date1, date2)
- Comparison of two dates.
- @param {Date} date1 - a Date object
- @param {Date} date2 - a Date object
- @returns {boolean} whether the dates are the same day (times are ignored)
const date1 = new Date(2017, 0, 2, 0); // Jan 2 2017 00:00:00
const date2 = new Date(2017, 0, 2, 23, 59); // Jan 2 2017 23:59:00
const date3 = new Date(2017, 0, 1, 23, 59); // Jan 1 2017 23:59:00
date.isSameDay(date1, date2); // => true
date.isSameDay(date1, date3); // => false
locale([code[, locale]])
- Change locale or setting a new locale definition.
- @param {string} [code] - language code
- @param {Object} [locale] - locale definition
- @returns {string} current language code
It returns a current language code if called without any parameters.
date.locale(); // => "en"
To switch to any other language, call it with a language code.
date.locale('es'); // Switch to Spanish
See LOCALE.md for details.
extend(extension)
- Locale extension.
- @param {Object} extension - locale definition
- @returns {void}
Extend a current locale. See EXTEND.md for details.
plugin(name[, extension])
- Plugin import or definition.
- @param {string} name - plugin name
- @param {Object} [extension] - locale definition
- @returns {void}
Plugin is a named locale definition defined with the extend()
. See PLUGINS.md for details.
Browser Support
Chrome, Firefox, Safari, Edge, and Internet Explorer 6+.
License
MIT