DateHelper
A high performant Swift Date Extension for creating, converting, comparing, or modifying dates.
Capabilities
Creating a Date from a String
Provides two initializers to create a date from string.
- detectFromString:
init?(detectFromString string: String)Uses NSDataDetector to detect a date from natural language in a string. It works similar to how Apple Mail detects dates. This initializer is not as efficient as fromString:format: and should not be used in collections like lists.
Date(detectFromString: "It happened on August 11 of 2009")
Date(detectFromString: "Tomorrow at 5:30 PM")
- fromString:format:
init?(fromString string: String, format:DateFormatType, timeZone: TimeZoneType = .local, locale: Locale = Foundation.Locale.current, isLenient: Bool = true)Initializes a date from a string using a strict or custom format that is cached, highly performant and thread safe.
Date(fromString: "2009", format: .isoYear)
Date(fromString: "2009-08", format: .isoYearMonth)
Date(fromString: "2009-08-11", format: .isoDate)
Date(fromString: "2009-08-11T06:00-07:00", format: .isoDateTime)
Date(fromString: "2009-08-11T06:00:00-07:00", format: .isoDateTimeSec)
Date(fromString: "2009-08-11T06:00:00.000-07:00", format: .isoDateTimeMilliSec)
Date(fromString: "/Date(1260123281843)/", format: .dotNet)
Date(fromString: "Fri, 09 Sep 2011 15:26:08 +0200", format: .rss)
Date(fromString: "09 Sep 2011 15:26:08 +0200", format: .altRSS)
Date(fromString: "Wed, 01 03 2017 06:43:19 -0500", format: .httpHeader)
Date(fromString: "16 July 1972 6:12:00", format: .custom("dd MMM yyyy HH:mm:ss"))
Convert a Date to a String
Provides three ways to convert a Date object to string
- toString(style:)
func toString(style:DateStyleType = .short) -> StringConverts a date to string based on a pre-desfined style
Date().toString(style: .short)
Date().toString(style: .medium)
Date().toString(style: .long)
Date().toString(style: .full)
Date().toString(style: .ordinalDay)
Date().toString(style: .weekday)
Date().toString(style: .shortWeekday)
Date().toString(style: .veryShortWeekday)
Date().toString(style: .month)
Date().toString(style: .shortMonth)
Date().toString(style: .veryShortMonth)
- toString(format:)
func toString(format: DateFormatType, timeZone: TimeZoneType = .local, locale: Locale = Locale.current) -> StringConverts a date to string based on a predefined or custom format
Date().toString(format: .custom("MMM d, yyyy"))
Date().toString(format: .custom("h:mm a"))
Date().toString(format: .custom("MMM d"))
Date().toString(format: .custom("MMM d"))
Date().toString(format: .isoYear)
Date().toString(format: .isoYearMonth)
Date().toString(format: .isoDate)
Date().toString(format: .isoDateTime)
Date().toString(format: .isoDateTimeSec)
Date().toString(format: .isoDateTimeMilliSec)
Date().toString(format: .dotNet)
Date().toString(format: .rss)
Date().toString(format: .altRSS)
Date().toString(format: .httpHeader)
- toString(dateStyle:timeStyle)
func toString(dateStyle: DateFormatter.Style, timeStyle: DateFormatter.Style, isRelative: Bool = false, timeZone: Foundation.TimeZone = Foundation.NSTimeZone.local, locale: Locale = Locale.current) -> StringConverts a date to string based on a predefined date and time style
Date().toString(dateStyle: .none, timeStyle: .short)
Date().toString(dateStyle: .short, timeStyle: .none)
Date().toString(dateStyle: .short, timeStyle: .short)
Date().toString(dateStyle: .medium, timeStyle: .medium)
Date().toString(dateStyle: .long, timeStyle: .long)
Date().toString(dateStyle: .full, timeStyle: .full)
Compare Dates
Provides common checks like isToday or isNextWeek. It can also check against another date like isSameDay or isEarlier.
- Quick Checks
Checks date against common scenarios
func compare(_ comparison: DateComparisonType) -> Bool
Date().compare(.isToday)
Date().compare(.isTomorrow)
Date().compare(.isYesterday)
Date().compare(.isThisWeek)
Date().compare(.isNextWeek)
Date().compare(.isLastWeek)
Date().compare(.isThisYear)
Date().compare(.isNextYear)
Date().compare(.isLastYear)
Date().compare(.isInTheFuture)
Date().compare(.isInThePast)
- Comparing Dates
Checks first date against second date
func compare(_ comparison: DateComparisonType) -> Bool
firstDate.compare(.isSameDay(as: secondDate))
firstDate.compare(.isSameWeek(as: secondDate))
firstDate.compare(.isSameMonth(as: secondDate))
firstDate.compare(.isSameYear(as: secondDate))
firstDate.compare(.isEarlier(than: secondDate))
firstDate.compare(.isLater(than: secondDate))
Adjust dates
Provides two functions for adjusting dates
- adjust(_ component:, offset:)
Offsets the specified date compontent of a date
func adjust(_ component:DateComponentType, offset:Int) -> Date
Date().adjust(.second, offset: 110)
Date().adjust(.minute, offset: 60)
Date().adjust(.hour, offset: 2)
Date().adjust(.day, offset: 1)
Date().adjust(.weekday, offset: 2)
Date().adjust(.nthWeekday, offset: 1)
Date().adjust(.week, offset: 1)
Date().adjust(.month, offset: 1)
Date().adjust(.year, offset: 1)
- adjust(hour:minute:second:)
Offsets the specified time component of the date
func adjust(hour: Int?, minute: Int?, second: Int?, day: Int? = nil, month: Int? = nil) -> Date
Date().adjust(hour: 12, minute: 0, second: 0)
Create Dates for…
Provides convenience date creators for common scenarios like endOfDay, startOfDay etc.
func dateFor(_ type:DateForType, calendar:Calendar = Calendar.current) -> Date
Date().dateFor(.startOfDay)
Date().dateFor(.endOfDay)
Date().dateFor(.startOfWeek)
Date().dateFor(.endOfWeek)
Date().dateFor(.startOfMonth)
Date().dateFor(.endOfMonth)
Date().dateFor(.tomorrow)
Date().dateFor(.yesterday)
Date().dateFor(.nearestMinute(minute:30))
Date().dateFor(.nearestHour(hour:2))
Date().dateFor(.startOfYear)
Date().dateFor(.endOfYear)
Time since…
Returns a number in the specified unit of measure since the secondary date.
func since(_ date:Date, in component:DateComponentType) -> Int64
Date().since(secondDate, in: .second)
Date().since(secondDate, in: .minute)
Date().since(secondDate, in: .hour)
Date().since(secondDate, in: .day)
Date().since(secondDate, in: .week)
Date().since(secondDate, in: .nthWeekday)
Date().since(secondDate, in: .week)
Date().since(secondDate, in: .month)
Date().since(secondDate, in: .year)
Miscellaneous
Setting the start day of the week
var calendar = Calendar(identifier: .gregorian)
calendar.firstWeekday = 2 // sets the week to start on Monday
Date().dateFor(.startOfWeek, calendar: calendar)
Extracting components from a date.
Date().component(.second)
Date().component(.minute)
Date().component(.hour)
Date().component(.day)
Date().component(.weekday)
Date().component(.nthWeekday)
Date().component(.month)
Date().component(.year)
Extracting miscellaneous items from a date.
Date().numberOfDaysInMonth()
Date().firstDayOfWeek()
Date().lastDayOfWeek()
Custom Component guide
Unicode Date Field Symbol Guide
| Format | Description | Example |
|---|---|---|
| “y” | 1 digit min year | 1, 42, 2017 |
| “yy” | 2 digit year | 01, 42, 17 |
| “yyy” | 3 digit min year | 001, 042, 2017 |
| “yyyy” | 4 digit min year | 0001, 0042, 2017 |
| “M” | 1 digit min month | 7, 12 |
| “MM” | 2 digit month | 07, 12 |
| “MMM” | 3 letter month abbr. | Jul, Dec |
| “MMMM” | Full month | July, December |
| “MMMMM” | 1 letter month abbr. | J, D |
| “d” | 1 digit min day | 4, 25 |
| “dd” | 2 digit day | 04, 25 |
| “E”, “EE”, “EEE” | 3 letter day name abbr. | Wed, Thu |
| “EEEE” | full day name | Wednesday, Thursday |
| “EEEEE” | 1 letter day name abbr. | W, T |
| “EEEEEE” | 2 letter day name abbr. | We, Th |
| “a” | Period of day | AM, PM |
| “h” | AM/PM 1 digit min hour | 5, 7 |
| “hh” | AM/PM 2 digit hour | 05, 07 |
| “H” | 24 hr 1 digit min hour | 17, 7 |
| “HH” | 24 hr 2 digit hour | 17, 07 |
| “m” | 1 digit min minute | 1, 40 |
| “mm” | 2 digit minute | 01, 40 |
| “s” | 1 digit min second | 1, 40 |
| “ss” | 2 digit second | 01, 40 |
| “S” | 10th’s place of fractional second | 123ms -> 1, 7ms -> 0 |
| “SS” | 10th’s & 100th’s place of fractional second | 123ms -> 12, 7ms -> 00 |
| “SSS” | 10th’s & 100th’s & 1,000’s place of fractional second | 123ms -> 123, 7ms -> 007 |
Requirements
Language: Swift 5.0 Minimum: iOS 11, tvOS 12, watchOS 4, macOS 10.14
Installation
Swift Package Manager https://github.com/melvitax/DateHelper.git Carthage github “melvitax/DateHelper” Manually Include DateHelper.swift in your project CocodaPods NO LONGER SUPPORTED
Author
Melvin Rivera
License
DateHelper is available under the MIT license. See the LICENSE file for more info.
