DateHelper

Converts the passed Date to an accurate number of months passed since the epoch start.

Ceils the passed Date value to the nearest increment value.

Optionally may ceil relative to a certain base time point.

For example DH.ceil(new Date('2020-01-01T09:35'), '30 min', new Date('2020-01-01T09:15')) would ceil to 9:45 because that's the closest higher integer number of 30 minute increments from the base.

Note that base is ignored when ceiling to weeks. Use weekStartDay argument which default to the configured weekStartDay dictates what the base of a week is

Coerces the passed Date between the passed minimum and maximum values.

Returns the end point of the passed date, that is 00:00:00 of the day after the passed date.

Floor the passed Date value to the nearest increment value.

Optionally may floor relative to a certain base time point.

For example DH.floor(new Date('2020-01-01T09:35'), '30 min', new Date('2020-01-01T09:15')) would floor to 9:15 because that's the closest lower integer number of 30 minute increments from the base.

Note that base is ignored when flooring to weeks. The configured weekStartDay dictates what the base of a week is.

Formats a range of dates using the specified format. Because two dates are involved, the format specifier uses the tokens S{} and E{}. The text contained between the {} is the format for the start date or end date, respectively. Text not inside these tokens is retained verbatim.

For example:

 DateHelper.formatRange(dates, 'S{DD MMM YYYY} - E{DD MMM YYYY}');

The above will format dates[0] based on the S{DD MMM YYYY} segment and dates[1] using E{DD MMM YYYY}. The ' - '` between these will remain between the two formatted dates.

Converts a millisecond time delta to an object structure. For example 1000 * 60 * 60 * 50 milliseconds the result would be as:

{
    day  : 2,
    hour : 2
}

Checks if value is a date object. Allows recognizing date object even from another context, like the top frame when used in an iframe.

Checks if date object is valid.

For example:

date = new Date('foo')
date instanceof Date // true
date.toString() // Invalid Date
isNaN(date) // true
DateHelper.isValidDate(date) // false

date = new Date()
date instanceof Date // true
date.toString() // Mon Jan 13 2020 18:27:38 GMT+0300 (GMT+03:00)
isNaN(date) // false
DateHelper.isValidDate(date) // true

Rounds the passed Date value to the nearest increment value.

Optionally may round relative to a certain base time point.

For example DH.round(new Date('2020-01-01T09:35'), '30 min', new Date('2020-01-01T09:15')) would round to 9:45 because that's the nearest integer number of 30 minute increments from the base.

Note that base is ignored when rounding to weeks. The configured weekStartDay dictates what the base of a week is.

Checks if this date is >= start and < end.

Checks if this date is >= start and <= end.

Compares two dates using the specified precision.

Compare two units. Returns 1 if first param is a greater unit than second param, -1 if the opposite is true or 0 if they're equal.

Returns true if date ranges intersect.

Determines if a date succeeds another.

Determines if a date precedes another.

Checks if two dates are equal.

Checks if date is the start of specified unit.

Determines if a date is today's date.

Returns true if the first time span completely 'covers' the second time span.

DateHelper.timeSpanContains(
    new Date(2010, 1, 2),
    new Date(2010, 1, 5),
    new Date(2010, 1, 3),
    new Date(2010, 1, 4)
) ==> true
DateHelper.timeSpanContains(
  new Date(2010, 1, 2),
  new Date(2010, 1, 5),
  new Date(2010, 1, 3),
  new Date(2010, 1, 6)
) ==> false

Add days, hours etc. to a date. Always clones the date, original will be left unaffected.

Removes time from a date (same as calling startOf(date)).

Creates a clone of the specified date

Constrains the date within a min and a max date.

Copies hours, minutes, seconds, milliseconds from one date to another.

Calculates the difference between two dates, in the specified unit.

Returns time with default year, month, and day (Jan 1, 2020).

Returns the elapsed milliseconds from the start of the specified date.

Sets a part of a date (in place).

Sets the date to the start of the specified unit, by default returning a clone of the date instead of changing it in place.

Converts the specified amount of one unit (fromUnit) into an amount of another unit (toUnit).

Converts the specified amount of desired unit into milliseconds. Can be called by only specifying a unit as the first argument, it then uses amount = 1.

For example:

asMilliseconds('hour') == asMilliseconds(1, 'hour')

Creates a date from a date definition object. The object can have the following properties:

• year
• month
• date (day in month)
• hours
• minutes
• seconds
• milliseconds
• amPm : 'am' or 'pm', implies 12-hour clock
• timeZone : offset from UTC in minutes

Converts a date to string with the specified format. Formats heavily inspired by https://momentjs.com. Available formats (input used for output below is new Date(2018,8,9,18,7,8,145)):

Some examples:

DateHelper.format(new Date(2019, 7, 16), 'dddd') -> Friday
DateHelper.format(new Date(2019, 7, 16, 14, 27), 'HH:mm') --> 14:27
DateHelper.format(new Date(2019, 7, 16, 14, 27), 'L HH') --> 2019-07-16 14

Using embedded text inside format string

Arbitrary text can be embedded in the format string by wrapping it with {}:

DateHelper.format(new Date(2019, 7, 16), '{It is }dddd{, yay!}') -> It is Friday, yay!

Converts a millisecond time delta to a human-readable form. For example 1000 * 60 * 60 * 50 milliseconds would be rendered as '2 days, 2 hours'.

Returns true for 24-hour format.

Returns a date created from the supplied string using the specified format. Will try to create even if format is left out, by first using the default format (see defaultFormat, by default YYYY-MM-DDTHH:mm:ssZ) and then using new Date(dateString). Supported tokens:

Predefined formats and functions used to parse tokens can be localized, see for example the swedish locale SvSE.js.

NOTE: If no date parameters are provided then Jan 01 2020 is used as a default date.

Parses a typed duration value according to locale rules.

The value is taken to be a string consisting of the numeric magnitude and the units:

• The numeric magnitude can be either an integer or a float value. Both ',' and '.' are valid decimal separators.
• The units may be a recognised unit abbreviation of this locale or the full local unit name.

For example: '2d', '2 d', '2 day', '2 days' will be turned into { magnitude : 2, unit : 'day' }'2.5d', '2,5 d', '2.5 day', '2,5 days' will be turned into { magnitude : 2.5, unit : 'day' }

NOTE: Doesn't work with complex values like '2 days, 2 hours'

Parses a typed unit name, for example 'ms' or 'hr' or 'yr' into the canonical form of the unit name which may be passed to add or diff.

Get number of days in the current month for the supplied date.

Get the specified part of a date.

Get the end of previous day.

Get the first date of the month for the supplied date.

Get the last date of the month for the supplied date.

Get an incremented date. Incrementation based on specified unit and optional amount.

Get the start of the next day.

Get week number for the date.

Get the latest of two dates.

Get the earliest of two dates.

Turns (10, 'day') into '10 days' etc.

Returns a duration of the timeframe in the given unit.

Returns a localized full name of the duration unit.

For example in the EN locale, for 'd' it will return either 'day' or 'days', depending on the plural argument

Preserves casing of first letter.

Returns a localized abbreviated form of the name of the duration unit. For example in the EN locale, for 'qrt' it will return 'q'.

Get the ratio between two units ( year, month -> 1/12 ).

Normalizes a unit for easier usage in conditionals. For example 'year', 'years', 'y' -> 'year'.