Xcode Swift am/pm time to 24 hour format - swift

Question

I am trying to convert an am/pm format time to a 24 hour format time
6:35 PM to 18:35
I tried this piece of code on playground but it doesn't seem to
work if I put the time alone
let dateAsString = "02/12/15, 6:35 PM"
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "HH"
let date = dateFormatter.dateFromString(dateAsString) //returns nil
Does anyone know how to accomplish this?

Answer 1

Just convert it to a date using NSDateFormatter and the "h:mm a" format and convert it back to a string using the "HH:mm" format. Check out this date formatting guide to familiarize yourself with this material.
let dateAsString = "6:35 PM"
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "h:mm a"
dateFormatter.locale = Locale(identifier: "en_US_POSIX") // fixes nil if device time in 24 hour format
let date = dateFormatter.dateFromString(dateAsString)
dateFormatter.dateFormat = "HH:mm"
let date24 = dateFormatter.stringFromDate(date!)

Answer 2

Swift 3
Time format 24 hours to 12 hours
let dateAsString = "13:15"
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "HH:mm"
let date = dateFormatter.date(from: dateAsString)
dateFormatter.dateFormat = "h:mm a"
let Date12 = dateFormatter.string(from: date!)
print("12 hour formatted Date:",Date12)
output will be 12 hour formatted Date: 1:15 PM
Time format 12 hours to 24 hours
let dateAsString = "1:15 PM"
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "h:mm a"
let date = dateFormatter.date(from: dateAsString)
dateFormatter.dateFormat = "HH:mm"
let Date24 = dateFormatter.string(from: date!)
print("24 hour formatted Date:",Date24)
output will be 24 hour formatted Date: 13:15

Answer 3

Swift 3 *
Code to convert 12 hours (i.e. AM and PM) to 24 hours format which includes-
Hours:Minutes:Seconds:AM/PM to Hours:Minutes:Seconds
func timeConversion24(time12: String) -> String {
let dateAsString = time12
let df = DateFormatter()
df.dateFormat = "hh:mm:ssa"
let date = df.date(from: dateAsString)
df.dateFormat = "HH:mm:ss"
let time24 = df.string(from: date!)
print(time24)
return time24
}
Input
07:05:45PM
Output
19:05:45
Similarly
Code to convert 24 hours to 12 hours (i.e. AM and PM) format which includes-
Hours:Minutes:Seconds to Hours:Minutes:Seconds:AM/PM
func timeConversion12(time24: String) -> String {
let dateAsString = time24
let df = DateFormatter()
df.dateFormat = "HH:mm:ss"
let date = df.date(from: dateAsString)
df.dateFormat = "hh:mm:ssa"
let time12 = df.string(from: date!)
print(time12)
return time12
}
Input
19:05:45
Output
07:05:45PM

Answer 4

Below is the swift 3 version of the solution -
let dateAsString = "6:35:58 PM"
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "h:mm:ss a"
let date = dateFormatter.date(from: dateAsString)
dateFormatter.dateFormat = "HH:mm:ss"
let date24 = dateFormatter.string(from: date!)
print(date24)

Answer 5

Here is the answer with more extra format.
** Xcode 12, Swift 5.3 **
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "HH:mm:ss"
var dateFromStr = dateFormatter.date(from: "12:16:45")!
dateFormatter.dateFormat = "hh:mm:ss a 'on' MMMM dd, yyyy"
//Output: 12:16:45 PM on January 01, 2000
dateFormatter.dateFormat = "E, d MMM yyyy HH:mm:ss Z"
//Output: Sat, 1 Jan 2000 12:16:45 +0600
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
//Output: 2000-01-01T12:16:45+0600
dateFormatter.dateFormat = "EEEE, MMM d, yyyy"
//Output: Saturday, Jan 1, 2000
dateFormatter.dateFormat = "MM-dd-yyyy HH:mm"
//Output: 01-01-2000 12:16
dateFormatter.dateFormat = "MMM d, h:mm a"
//Output: Jan 1, 12:16 PM
dateFormatter.dateFormat = "HH:mm:ss.SSS"
//Output: 12:16:45.000
dateFormatter.dateFormat = "MMM d, yyyy"
//Output: Jan 1, 2000
dateFormatter.dateFormat = "MM/dd/yyyy"
//Output: 01/01/2000
dateFormatter.dateFormat = "hh:mm:ss a"
//Output: 12:16:45 PM
dateFormatter.dateFormat = "MMMM yyyy"
//Output: January 2000
dateFormatter.dateFormat = "dd.MM.yy"
//Output: 01.01.00
//Output: Customisable AP/PM symbols
dateFormatter.amSymbol = "am"
dateFormatter.pmSymbol = "Pm"
dateFormatter.dateFormat = "a"
//Output: Pm
// Usage
var timeFromDate = dateFormatter.string(from: dateFromStr)
print(timeFromDate)

Answer 6

Swift version 3.0.2 , Xcode Version 8.2.1 (8C1002) (12 hr format ):
func getTodayString() -> String{
let formatter = DateFormatter()
formatter.dateFormat = "h:mm:ss a "
formatter.amSymbol = "AM"
formatter.pmSymbol = "PM"
let currentDateStr = formatter.string(from: Date())
print(currentDateStr)
return currentDateStr
}
OUTPUT : 12:41:42 AM
Feel free to comment. Thanks

Answer 7

Use this function for date conversion, its working fine when your device in 24/12 hr format
See https://developer.apple.com/library/archive/qa/qa1480/_index.html
func convertDateFormatter(fromFormat:String,toFormat:String,_ dateString: String) -> String{
let formatter = DateFormatter()
formatter.locale = Locale(identifier: "en_US_POSIX")
formatter.dateFormat = fromFormat
let date = formatter.date(from: dateString)
formatter.dateFormat = toFormat
return date != nil ? formatter.string(from: date!) : ""
}

Answer 8

Unfortunately apple priority the device date format, so in some cases against what you put, swift change your format to 12hrs
To fix this is necessary to use setLocalizedDateFormatFromTemplate instead of dateFormat an hide the AM and PM
let formatter = DateFormatter()
formatter.setLocalizedDateFormatFromTemplate("HH:mm:ss a")
formatter.amSymbol = ""
formatter.pmSymbol = ""
formatter.timeZone = TimeZone(secondsFromGMT: 0)
var prettyDate = formatter.string(from: Date())
You can check a very useful post with more information detailed in
https://prograils.com/posts/the-curious-case-of-the-24-hour-time-format-in-swift

Answer 9

Here is code for other way around
For Swift 3
func amAppend(str:String) -> String{
var temp = str
var strArr = str.characters.split{$0 == ":"}.map(String.init)
var hour = Int(strArr[0])!
var min = Int(strArr[1])!
if(hour > 12){
temp = temp + "PM"
}
else{
temp = temp + "AM"
}
return temp
}

Answer 10

let calendar = Calendar.current
let hours = calendar.component(.hour, from: Date())
let minutes = calendar.component(.minute, from: Date())
let seconds = calendar.component(.second, from: Date())

Answer 11

I am using a function here in my case by which I am updating a label with the normal time format and after that I am storing the selected time's 24hr format to do some another tasks..
Here is my code...
func timeUpdate(sender: NSDate)
{
let timeSave = NSDateFormatter() //Creating first object to update time label as 12hr format with AM/PM
timeSave.timeStyle = NSDateFormatterStyle.ShortStyle //Setting the style for the time selection.
self.TimeShowOutlet.text = timeSave.stringFromDate(sender) // Getting the string from the selected time and updating the label as 1:40 PM
let timeCheck = NSDateFormatter() //Creating another object to store time in 24hr format.
timeCheck.dateFormat = "HH:mm:ss" //Setting the format for the time save.
let time = timeCheck.stringFromDate(sender) //Getting the time string as 13:40:00
self.timeSelectedForCheckAvailability = time //At last saving the 24hr format time for further task.
}
After writing this function you can call this where you are choosing the time from date/time picker.
Thanks,
Hope this helped.

Answer 12

this is similar to our friends answer: https://stackoverflow.com/a/43801717/2796837 but using all our internet friends ideas I came up with the following more complete singular solution:
let amPmFormat = "h:mm a"
let twentyFourHFormat = "HH:mm"
func hourMinuteParser(date: Date) -> KotlinInt{
let formatter = DateFormatter()
if DateFormatter.dateFormat(fromTemplate: "j",options:0, locale: Locale.current)!.contains("a") {
formatter.dateFormat = amPmFormat
}else{
formatter.dateFormat = twentyFourHFormat
}
let stringTime = formatter.string(from: date)
let time = formatter.date(from: stringTime)
formatter.dateFormat = twentyFourHFormat
let time24 = formatter.string(from: time!)
let timeWithoutSpecialCharacters = time24.replacingOccurrences(of: ":", with: "")
let int2 = Int32(timeWithoutSpecialCharacters) ?? 0
return KotlinInt(int: int2)
}
This will parse your time even independent of the format it comes and outputs it into HH:mm, you could change the third format change into whatever you would want.