I am trying to get an Int value for Hour from a string.
let time = 13:24
func getNtfHour() -> Date{
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "HH"
let result = dateFormatter.date(from: time)!
return result //2000-01-01 08:24:00 +0000
}
As you can see my current code return a whole date and the time does not match with the string. How do I fix it?
edit: I managed to to this by using date components
let time = 13:24
func getNtfHour() -> Int{
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "HH:mm"
let result = dateFormatter.date(from: time)!
let calendar = Calendar.current.component(.hour, from: result)
return calendar //13
}
As a time string is actually not related to a Dateformatter an easier way is to parse the string directly.
If the hour has always two digits
let time = "13:24"
let hour = Int(time.prefix(2))
or otherwise
let time = "13:24"
if let range = time.range(of: "^\\d+", options: .regularExpression) {
let hour = Int(time[range])
}
Related
I get a crash when running and it points at the dateFormmater.timezone.
The error in the console is:
Could not cast value of type 'Swift.Optional' (0x1192bf4a8) to 'NSTimeZone' (0x1192c0270).
the value of rowEvents.date is "1480134638.0"
Im trying to pull out a Unix timestamp from Firebase saved as a string. Convert it to Date and again save it as a string so I can post it on a cell label.
I got this code from StackOverflow. I plugged in my data and everything is all good until I run it. I guess everything is not all good...
if let lastUpdated : String = rowEvents.date {
let epocTime = TimeInterval(lastUpdated)! / 1000 // convert it from milliseconds dividing it by 1000
let unixTimestamp = NSDate(timeIntervalSince1970: epocTime) //convert unix timestamp to Date
let dateFormatter = DateFormatter()
dateFormatter.timeZone = NSTimeZone() as TimeZone!
dateFormatter.locale = NSLocale.current // NSLocale(localeIdentifier: "en_US_POSIX")
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
dateFormatter.date(from: String(describing: unixTimestamp))
let updatedTimeStamp = unixTimestamp
let cellDate = DateFormatter.localizedString(from: updatedTimeStamp as Date, dateStyle: DateFormatter.Style.full, timeStyle: DateFormatter.Style.medium)
cell.subtitleLabel.text = cellDate
}
The result came from this code here:
let myTimeStamp = self.datePicker?.date.timeIntervalSince1970
let calendarDate = String(describing: myTimeStamp! /** 1000*/)
You can convert unixTimestamp to date using Date(timeIntervalSince1970:).
let unixTimestamp = 1480134638.0
let date = Date(timeIntervalSince1970: unixTimestamp)
If you want to display date in string with specific formate than you can use DateFormatter like this way.
let date = Date(timeIntervalSince1970: unixtimeInterval)
let dateFormatter = DateFormatter()
dateFormatter.timeZone = TimeZone(abbreviation: "GMT") //Set timezone that you want
dateFormatter.locale = NSLocale.current
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm" //Specify your format that you want
let strDate = dateFormatter.string(from: date)
The problem is the line dateFormatter.timeZone = NSTimeZone() as TimeZone!.
Simply use TimeZone instead of NSTimeZone like
dateFormatter.timeZone = TimeZone.current and your code will work.
You might also remove your / 1000 because 1480134638.0 looks more like seconds than milliseconds (since 1970).
Swift 4.1. I created a function. Just pass you timeStamp in function param and function will return data in string data type. You can add more properties to DateFormatter object.
func getDateFromTimeStamp(timeStamp : Double) -> String {
let date = NSDate(timeIntervalSince1970: timeStamp / 1000)
let dayTimePeriodFormatter = DateFormatter()
dayTimePeriodFormatter.dateFormat = "dd MMM YY, hh:mm a"
// UnComment below to get only time
// dayTimePeriodFormatter.dateFormat = "hh:mm a"
let dateString = dayTimePeriodFormatter.string(from: date as Date)
return dateString
}
Using playground all I did was this.
let epochTime = 1547855446
let newTime = Date(timeIntervalSince1970: TimeInterval(epochTime))
print(newTime)
Returns this - 2019-01-18 23:50:46 +0000
extension Double{
func convertDate(formate: String) -> String {
let date = (timeIntervalSince1970: self)
let dateFormatter = DateFormatter()
dateFormatter.timeZone = TimeZone.current
dateFormatter.locale = NSLocale(localeIdentifier: "(your localization language)" ) as Locale //localization language
dateFormatter.dateFormat = formate //Specify your format that you want let
strDate = dateFormatter.string(from: date)
return strDate
}
}
//usage
let timeStamp:Double = Double(1595407043)
print(timeStamp.convertDate(formate: "EEEE dd/MM/YYY"))
This solution is valid for swift 3 -> 4.2 :
you can add an extension on the Double that returns the date formatted:
extension Double {
// returns the date formatted.
var dateFormatted : String? {
let date = Date(timeIntervalSince1970: self)
let dateFormatter = DateFormatter()
dateFormatter.timeStyle = DateFormatter.Style.none //Set time style
dateFormatter.dateStyle = DateFormatter.Style.short //Set date style
return dateFormatter.string(from: date)
}
// returns the date formatted according to the format string provided.
func dateFormatted(withFormat format : String) -> String{
let date = Date(timeIntervalSince1970: self)
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = format
return dateFormatter.string(from: date)
}
}
example on the above :
let timeStamp = 82749029.0
print(timeStamp. dateFormatted)
//output
//12/11/1994
let timeStamp = 82749029.0
print(timeStamp. dateFormatted(withFormat : "MM-dd-yyyy HH:mm"))
//output
//12-11-1994 13:04
func getMonYearDateFormat() -> String {
let dateFormatter = DateFormatter()//EEEE, d, MMM
dateFormatter.dateFormat = is24Hour() ? "yyyy-MM-dd' 'HH:mm:ss" : "yyyy-MM-dd' 'h:mm:ss a"
dateFormatter.timeZone = TimeZone.current
dateFormatter.locale = Locale.current
guard let oldDate = dateFormatter.date(from: self) else { return "" }
let convertDateFormatter = DateFormatter()
convertDateFormatter.dateFormat = "MMMM yyyy"
return convertDateFormatter.string(from: oldDate)
}
I show month and year as title in table view. I wrote this function to convert the date of the relevant card to month and year. If the device is in the 24-hour time zone, the function works properly. However, if the device is in the 12th time zone, it returns blank and I cannot see the month and year of the relevant card. I couldn't find the part that I wrote incorrectly in the function.
I've tested your code with 12 hour format and it works. The only thing I've. change is to use the 12 hour format without call is24Hour() because you did not provide that code. So I suspect the point of failure is the is24Hour() function.
As mentioned in the comments I would recommend you to investigate how you get this string and if possibly use the original Date object instead if it exists but below is a solution that I think handles the 12 vs 24h issue in an efficient way.
The logic is to first convert using 24h and if that returns nil then convert using the 12h format.
I have declared all formatters I use as static properties so they only get created one since creating a DateFormatter is expensive
extension String {
private static let formatter24: DateFormatter = {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd' 'HH:mm:ss"
return dateFormatter
}()
private static let formatter12: DateFormatter = {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd' 'h:mm:ss a"
return dateFormatter
}()
private static let formatterMonthYear: DateFormatter = {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "MMMM yyyy"
return dateFormatter
}()
func getMonYearDateFormat() -> String {
let date = Self.formatter24.date(from: self) ?? Self.formatter12.date(from: self)
guard let date else { return "" }
return Self.formatterMonthYear.string(from: date)
}
}
iOS Date() returns date with at least microsecond precision.
I checked this statement by calling Date().timeIntervalSince1970 which results in 1490891661.074981
Then I need to convert date into string with microsecond precision.
I am using DateFormatter in following way:
let formatter = DateFormatter()
formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss.SSSSSSZZZZZ"
print(formatter.string(from: date))
which results in
"2017-03-30T16:34:21.075000Z"
Now if we compare two results:
1490891661.074981 and "2017-03-30T16:34:21.075000Z"
we can notice that DateFormatter rounds date to millisecond precision while still presenting zeros for microseconds.
Does anybody know how to configure DateFormatter so I can keep microseconds and get correct result: "2017-03-30T16:34:21.074981Z"?
Thanks to #MartinR for solving first half of my problem and to #ForestKunecke for giving me tips how to solve second half of the problem.
Based on their help I created ready to use solution which converts date from string and vice versa with microsecond precision:
public final class MicrosecondPrecisionDateFormatter: DateFormatter {
private let microsecondsPrefix = "."
override public init() {
super.init()
locale = Locale(identifier: "en_US_POSIX")
timeZone = TimeZone(secondsFromGMT: 0)
}
required public init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
override public func string(from date: Date) -> String {
dateFormat = "yyyy-MM-dd'T'HH:mm:ss"
let components = calendar.dateComponents(Set([Calendar.Component.nanosecond]), from: date)
let nanosecondsInMicrosecond = Double(1000)
let microseconds = lrint(Double(components.nanosecond!) / nanosecondsInMicrosecond)
// Subtract nanoseconds from date to ensure string(from: Date) doesn't attempt faulty rounding.
let updatedDate = calendar.date(byAdding: .nanosecond, value: -(components.nanosecond!), to: date)!
let dateTimeString = super.string(from: updatedDate)
let string = String(format: "%#.%06ldZ",
dateTimeString,
microseconds)
return string
}
override public func date(from string: String) -> Date? {
dateFormat = "yyyy-MM-dd'T'HH:mm:ssZZZZZ"
guard let microsecondsPrefixRange = string.range(of: microsecondsPrefix) else { return nil }
let microsecondsWithTimeZoneString = String(string.suffix(from: microsecondsPrefixRange.upperBound))
let nonDigitsCharacterSet = CharacterSet.decimalDigits.inverted
guard let timeZoneRangePrefixRange = microsecondsWithTimeZoneString.rangeOfCharacter(from: nonDigitsCharacterSet) else { return nil }
let microsecondsString = String(microsecondsWithTimeZoneString.prefix(upTo: timeZoneRangePrefixRange.lowerBound))
guard let microsecondsCount = Double(microsecondsString) else { return nil }
let dateStringExludingMicroseconds = string
.replacingOccurrences(of: microsecondsString, with: "")
.replacingOccurrences(of: microsecondsPrefix, with: "")
guard let date = super.date(from: dateStringExludingMicroseconds) else { return nil }
let microsecondsInSecond = Double(1000000)
let dateWithMicroseconds = date + microsecondsCount / microsecondsInSecond
return dateWithMicroseconds
}
}
Usage:
let formatter = MicrosecondPrecisionDateFormatter()
let date = Date(timeIntervalSince1970: 1490891661.074981)
let formattedString = formatter.string(from: date) // 2017-03-30T16:34:21.074981Z
The resolution of (NS)DateFormatter is limited to milliseconds, compare
NSDateFormatter milliseconds bug. A possible solution is to retrieve all date components (up to
nanoseconds) as numbers and do a custom string formatting. The date formatter can still be used for the timezone string.
Example:
let date = Date(timeIntervalSince1970: 1490891661.074981)
let formatter = DateFormatter()
formatter.dateFormat = "ZZZZZ"
let tzString = formatter.string(from: date)
let cal = Calendar.current
let comps = cal.dateComponents([.year, .month, .day, .hour, .minute, .second, .nanosecond],
from: date)
let microSeconds = lrint(Double(comps.nanosecond!)/1000) // Divide by 1000 and round
let formatted = String(format: "%04ld-%02ld-%02ldT%02ld:%02ld:%02ld.%06ld",
comps.year!, comps.month!, comps.day!,
comps.hour!, comps.minute!, comps.second!,
microSeconds) + tzString
print(formatted) // 2017-03-30T18:34:21.074981+02:00
Solution by #Vlad Papko has some issue:
For dates like following:
2019-02-01T00:01:54.3684Z
it can make string with extra zero:
2019-02-01T00:01:54.03684Z
Here is fixed solution, it's ugly, but works without issues:
override public func string(from date: Date) -> String {
dateFormat = "yyyy-MM-dd'T'HH:mm:ss"
let components = calendar.dateComponents(Set([Calendar.Component.nanosecond]), from: date)
let nanosecondsInMicrosecond = Double(1000)
let microseconds = lrint(Double(components.nanosecond!) / nanosecondsInMicrosecond)
// Subtract nanoseconds from date to ensure string(from: Date) doesn't attempt faulty rounding.
let updatedDate = calendar.date(byAdding: .nanosecond, value: -(components.nanosecond!), to: date)!
let dateTimeString = super.string(from: updatedDate)
let stingWithMicroseconds = "\(date.timeIntervalSinceReferenceDate)"
let dotIndex = stingWithMicroseconds.lastIndex(of: ".")!
let hasZero = stingWithMicroseconds[stingWithMicroseconds.index(after: dotIndex)] == "0"
let format = hasZero ? "%#.%06ldZ" : "%#.%6ldZ"
let string = String(format: format,
dateTimeString,
microseconds)
return string
}
It is a bit of a hack, but not that complex and 100% Swift:
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss.'MICROS'xx"
dateFormatter.locale = Locale(identifier: "en_US_POSIX")
// Get the number of microseconds with a precision of 6 digits
let now = Date()
let dateParts = Calendar.current.dateComponents([.nanosecond], from: now)
let microSeconds = Int((Double(dateParts.nanosecond!) / 1000).rounded(.toNearestOrEven))
let microSecPart = String(microSeconds).padding(toLength: 6, withPad: "0", startingAt: 0)
// Format the date and add in the microseconds
var timestamp = dateFormatter.string(from: now)
timestamp = timestamp.replacingOccurrences(of: "MICROS", with: microSecPart)
I have an API that returns data including a timestamp for that record.
In swift I have the timestamp element loaded and converted into a double and can then convert that into time. I want to be able to return the time if the date of the record is today and return the date if the record is not today.
See below:
let unixTimeString:Double = Double(rowData["Timestamp"] as! String)!
let date = NSDate(timeIntervalSince1970: unixTimeString) // This is on EST time and has not yet been localised.
var dateFormatter = NSDateFormatter()
dateFormatter.timeStyle = .ShortStyle
dateFormatter.doesRelativeDateFormatting = true
// If the date is today then just display the time, if the date is not today display the date and change the text color to grey.
var stringTimestampResponse = dateFormatter.stringFromDate(date)
cell.timestampLabel.text = String(stringTimestampResponse)
Do I use NSCalendar to see if 'date' is today and then do something?
How do you then localise the time so that its correct for the user rather than server time?
There is a handy function on NSCalendar that tells you whether an NSDate is in today or not (requires at least iOS 8) isDateInToday()
To see it working, put this into a playground:
// Create a couple of unix dates.
let timeIntervalToday: NSTimeInterval = NSDate().timeIntervalSince1970
let timeIntervalLastYear: NSTimeInterval = 1438435830
// This is just to show what the dates are.
let now = NSDate(timeIntervalSince1970: timeIntervalToday)
let then = NSDate(timeIntervalSince1970: timeIntervalLastYear)
// This is the function to show a formatted date from the timestamp
func displayTimestamp(ts: Double) -> String {
let date = NSDate(timeIntervalSince1970: ts)
let formatter = NSDateFormatter()
formatter.timeZone = NSTimeZone.systemTimeZone()
if NSCalendar.currentCalendar().isDateInToday(date) {
formatter.dateStyle = .NoStyle
formatter.timeStyle = .ShortStyle
} else {
formatter.dateStyle = .ShortStyle
formatter.timeStyle = .NoStyle
}
return formatter.stringFromDate(date)
}
// This should just show the time.
displayTimestamp(timeIntervalToday)
// This should just show the date.
displayTimestamp(timeIntervalLastYear)
Or, if you just want to see what it looks like without running it yourself:
Abizern's answer in Swift 3:
import UIKit
let timeIntervalToday: TimeInterval = Date().timeIntervalSince1970
let timeIntervalLastYear: TimeInterval = 1438435830
// This is just to show what the dates are.
let now = Date(timeIntervalSince1970: timeIntervalToday)
let then = Date(timeIntervalSince1970: timeIntervalLastYear)
// This is the function to show a formatted date from the timestamp
func displayTimestamp(ts: Double) -> String {
let date = Date(timeIntervalSince1970: ts)
let formatter = DateFormatter()
//formatter.timeZone = NSTimeZone.system
if Calendar.current.isDateInToday(date) {
formatter.dateStyle = .none
formatter.timeStyle = .short
} else {
formatter.dateStyle = .short
formatter.timeStyle = .none
}
return formatter.string(from: date)
}
// This should just show the time.
displayTimestamp(ts: timeIntervalToday)
// This should just show the date.
displayTimestamp(ts: timeIntervalLastYear)
I'm having problems with NSDate in Swift.
I JSON a date formatted in Y-m-d from my database. This is stored as a string called survey_date
I then convert the string to a NSDate using dateFormatter
I want to work out the amount of days between the survey_date and NOW
Error in my script is endDate is ambiguous expression without more context.
Here is my script:
var survey_date = prefs.valueForKey("SURVEY_DATE") as! String
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd"
var date = dateFormatter.dateFromString(survey_date) as NSDate!
let outputDate = dateFormatter.stringFromDate(date)
println(outputDate)
let start = outputDate
let end = NSDate()
let dateFormatter2 = NSDateFormatter()
dateFormatter2.dateFormat = "yyyy-MM-dd"
let startDate:NSDate = dateFormatter2.dateFromString(start)!
let endDate:NSDate = dateFormatter2.dateFromString(end)!
let cal = NSCalendar.currentCalendar()
let unit:NSCalendarUnit = .CalendarUnitDay
let components = cal.components(unit, fromDate: startDate, toDate: endDate, options: nil)
println(components)
Secondly, I also want to be able to convert the date when possible to a different format - for example d m, Y. This is pretty simple to do in PHP but I can't find a way of doing it in Swift? I don't want to have to send extra data through JSON (i.e. create a $formatted_date) but it looks like this is my only option (which I know is messy and I will get told off for!)
You get a compiler error in
let endDate:NSDate = dateFormatter2.dateFromString(end)!
because dateFromString() is called with a date instead of a string,
which makes no sense.
Your computation is a bit too complicated, you can shorten it to
let survey_date = "2015-05-01"
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd"
if let startDate = dateFormatter.dateFromString(survey_date) {
let endDate = NSDate()
let cal = NSCalendar.currentCalendar()
let components = cal.components(.CalendarUnitDay, fromDate: startDate, toDate: endDate, options: nil)
let days = components.day
println(days)
} else {
println("invalid input")
}
If you want to convert the date into a different format then
(as Leo already said in a comment), use stringFromDate() with
a second date formatter, e.g.
let dateFormatter2 = NSDateFormatter()
dateFormatter2.dateFormat = "d MM, Y"
let formattedStartDate = dateFormatter2.stringFromDate(startDate)
println(formattedStartDate)
Here's something you may find handy. I was working on an app that did a lot of date calculations, and therefore was making lots of calls to NSCalendar's components(_:fromDate:toDate:options:) method. This doesn't feel terribly Swift-like, so I overloaded the - operator to do date subtractions:
func -(lhs: NSDate, rhs: NSDate) -> NSDateComponents
{
let components: NSCalendarUnit =
.CalendarUnitSecond |
.CalendarUnitMinute |
.CalendarUnitHour |
.CalendarUnitDay
return NSCalendar.currentCalendar().components(components,
fromDate: rhs,
toDate: lhs,
options: nil)
}
This lets you find the difference between any two dates/times by simple subtraction. Here's a quick example:
// MySQL date formatter
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd"
// Let's create a couple of dates that we know are one day apart
let christmas2015 = dateFormatter.dateFromString("2015-12-25")!
let christmasEve2015 = dateFormatter.dateFromString("2015-12-24")!
let difference = christmas2015 - christmasEve2015
let daysBetween = difference.day // this value is 1