i'm having an array fill with date string, which i would like to go through and check whether the date is today or yesterday. The date string could look like following:
2015-04-10 22:07:00
So far i've tried just to convert it using dateFormatter, but it keeps returning nil
var dateString = arrayNews[0][0].date as NSString
var dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd hh:mm:ss"
var date = dateFormatter.dateFromString(dateString as String)
println(date)
the sudo code i would like to look something like this
if dateString == currentDate
date = "Today, hh:mm"
else if dateString == currentDate(-1)
date = "Yesterday, hh:mm
else
date = dd. MM, hh:mm
in the else statement the date could be 1. April, 12:00
How can i achieve such a logic?
Without the logic
func getDate(dateStr:String, format:String = "yyyy-MM-dd HH:mm:ss") -> NSString {
var dateFmt = NSDateFormatter()
dateFmt.timeZone = NSTimeZone.defaultTimeZone()
dateFmt.dateFormat = format
let newsDate = dateFmt.dateFromString(dateStr)!
let date = NSDate();
let dateFormatter = NSDateFormatter()
dateFormatter.timeZone = NSTimeZone()
let localDate = dateFormatter.stringFromDate(date)
return ""
}
You have to use yyyy-MM-dd HH:mm:ss instead of yyyy-MM-dd hh:mm:ss
HH: 24h format
hh: 12h format (with AM/PM)
Pay attention with dateFormatter, by default, it use localtime zone.
println() shows the value for GMT time, which is hold by NSDate.
It means, without specifying timezone, when you convert your string 2015-04-10 22:07:00 to NSDatetime, it return a data which is the time at your local time zone is 2015-04-10 22:07:00. As NSDate holds date time in GMT, you will see a different value when you show the value of that NSDate with println().
If your timezone is GMT+2 (2h earlier than GMT), when it's 22h:07 in your place, the GMT time is 20h:07. When you call println() on that NSDate, you see 2015-04-10 20:07:00
To compare 2 NSDate:
let calendar = NSCalendar(identifier: NSCalendarIdentifierGregorian)
let compareResult = calendar?.compareDate(date, toDate: date2, toUnitGranularity: NSCalendarUnit.CalendarUnitDay)
if (compareResult == NSComparisonResult.OrderedSame) {
println("yes")
} else {
println("no")
}
//to get yesterday, using NSCalendar:
let yesterday = calendar?.dateByAddingUnit(NSCalendarUnit.CalendarUnitDay, value: -1, toDate: date, options: NSCalendarOptions.MatchStrictly)
Related
i am passing "01/12/2017" in the fromDate.text(textfield), but receiving unexpected output.
let formatter = DateFormatter.init()
formatter.dateFormat = "dd/mm/yyyy"
startDate = formatter.date(from: fromDate.text!)
print("startDate = \(startDate)")
output is : 31/12/2016
The format of date should be dd/MM/yyyy not dd/mm/yyyy. The mm indicates the minutes and MM indicates the month.
And also add the below line in your code
formatter.timeZone = TimeZone(abbreviation: "GMT+0:00")
This line of code set time zone. If you not, then you get 30/11/2017 in output.
The reason behind this is when string date not contain time then formatter assume that it is midnight and you also not given the timezone so it will take current timezone.
It has to be dd/MM/yyyy dateformat. MM in capital.
func convertToString(of dateTo: Date) -> String {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "dd/MM/yyyy" //Your New Date format as per requirement change it own
let newDate: String = dateFormatter.string(from: dateTo) //pass Date here
print(newDate) //New formatted Date string
return newDate
}
**
GET GMT DATE STRING
**
func getGMTString(dateAsDate:NSDate) -> String
{
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss zzz"//this your string date format
// dateFormatter.locale = NSLocale.currentLocale()
// dateFormatter.timeZone = NSTimeZone(name: "GMT")
let date = dateFormatter.stringFromDate(dateAsDate)
return date
}
OUTPUT
startDate---2016-06-29 00:00:00 GMT+5:30
endDate----2016-06-30 03:57:39 GMT+5:30
NOW TRYING to get GMT Date object from output string
func getGMTDate(string:String) -> NSDate {
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd HH:mm:ss zzz"//this your string date format
// dateFormatter.timeZone = NSTimeZone(abbreviation: "GMT")!
// dateFormatter.locale = NSLocale.currentLocale()
let date = dateFormatter.dateFromString(string)
return date!
}
PROBLEM: OUTPUT DATE OBJECT MESS
startDateOBJECT---2016-06-28 18:30:00 +0000 endDateOBJECT----2016-06-30 17:30:00 +0000
Unable to figure what is going wrong
I don't understand your step 3. I looks like you're using NSLog or a Swift print to display the resulting date. That is ALWAYS done in UTC.
If you want to view your date in a different format, or with your local time zone, you need a second date formatter to convert the NSDate to an output date string.
Here's the flow:
input date string -> input date formatter -> NSDate
NSDate -> output date formatter -> display date in local time zone
I get a NSDate from a UIDatePicker (timePicker) which is converted to the users time zone but it is one hour off because I'm in Summer Time.
So I tried to check if the User is in Summer Time if yes it should add the time to the NSDate/dateInUserTimezone.
How can I achieve this?
func convertTimeZone() ->NSDate {
var date = timePicker.date
print(date)
var formatter = NSDateFormatter()
let timeZone = NSTimeZone(abbreviation: userTimeZone())
formatter.timeZone = timeZone
formatter.dateFormat = "HH:mm:ss"
var isDaylightSavingTime: Bool {
return NSTimeZone.localTimeZone().daylightSavingTime
}
print(isDaylightSavingTime)
var daylightSavingTimeOffset: NSTimeInterval {
return NSTimeZone.localTimeZone().daylightSavingTimeOffset
}
let dateInUserTimezone = formatter.dateFromString(formatter.stringFromDate(date))
return dateInUserTimezone!
}
func userTimeZone() -> String {
return NSTimeZone.localTimeZone().abbreviation ?? ""
}
NSDate is inherently in UTC (it has no timezone). Best to save/transfer your dates in UTC. Then, you can convert this UTC time stamp to any time zone of your preference. Instead of detecting whether the user is DST or not, try converting to your preferred time zone. Here's an example of how you would convert any date to local time zone.
var date = ...
var myTimeZone = NSTimeZone.localTimeZone()
var df = NSDateFormatter()
df.timeZone = myTimeZone
df.dateFormat = "yyyy.MM.dd G 'at' HH:mm:ss zzz"
df.stringFromDate(date)
I have this date 2015-11-06T18:00:00-0500
My format is yyyy-MM-dd'T'HH:mm:ssZ
i try
let startDateString = "2015-11-06T18:00:00-0500"
let format = NSDateFormatter()
format.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
let startDateBtnEnd = format.dateFromString(startDateString)
println("startDateBtnEnd 2 \(startDateBtnEnd)")
But the log is
startDateBtnEnd 2 Optional(2015-11-07 00:00:00 +0000)
NSDate stores dates in UTC. You can convert it to the same moment in time in any timezone. But after losing too many neurons to mentally convert NSDate from one timezone to another, I decided to add my own extension to NSDate to print it out in the local timezone instead:
extension NSDate {
func toString(timeZone: NSTimeZone = NSTimeZone.localTimeZone()) -> String {
let formatter = NSDateFormatter()
formatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
formatter.timeZone = timeZone
return formatter.stringFromDate(self)
}
}
// Usage:
print("startDateBtnEnd 2 \(startDateBtnEnd.toString())")
I want to get a date that is represented in a String with a time zone GMT+1 and display it on screen with the local time zone GMT+10.
I have 2 methods, one is for create a date from a String (with GMT+1 timeZone), the other one is to format the date into a String (with localTimeZone GMT+10):
func dateFromString(dateString: String) -> NSDate? {
let dateFormatter = NSDateFormatter()
dateFormatter.timeZone = NSTimeZone(abbreviation: "GMT+1")
dateFormatter.dateFormat = "M/d/yyyy hh:mma"
return dateFormatter.dateFromString(dateString)
}
func stringFromDate(date: NSDate) -> String {
let dateFormatter = NSDateFormatter()
dateFormatter.timeZone = NSTimeZone.localTimeZone()
dateFormatter.timeStyle = NSDateFormatterStyle.ShortStyle
return dateFormatter.stringFromDate(date)
}
In the playground, when I do this:
let date = dateFromString("4/8/2015 1:29am")!
println(date)
println(stringFromDate(date))
I get the following output on the right side:
"Apr 8, 2015, 1:29 AM"
"2015-04-07 15:29:00 +0000"
"1:29 AM"
I don't understand why I don't get what I am expecting and looking for:
"Apr 8, 2015, 1:29 AM"
"2015-04-08 10:29:00 +0000"
"10:29 AM"
What's wrong?
Input formatters need the time zone in their string. Like so:
func dateFromString(dateString: String) -> NSDate? {
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "M/d/yyyy hh:mma z"
return dateFormatter.dateFromString(dateString)
}
let date = dateFromString("4/8/2015 1:29am GMT+01")!
Also note that NSTimeZone names have a two digit offset. Compare in the playground
var oops = NSTimeZone(abbreviation: "GMT+1")
var righteous = NSTimeZone(abbreviation: "GMT+01")
The first is nil, the second is not.
I wouldn't trust the formatting of a time stamp that the debugger prints. In my experience dates are always in UTC regardless of the time zone you set according to the log. Try adding the date as a string to a label on the project and see if it's right.
The reasoning behind this as far as I know is that when you print to the log, all it's doing is calling -description. In the case of NSDate this will return in UTC by definition.