Convert string to date in Swift

问题

How can I convert this string \"2016-04-14T10:44:00+0000\" into an NSDate and keep only the year, month, day, hour?

The T in the middle of it really throws off what I am used to when working with dates.

回答1:

Convert the ISO8601 string to date

let isoDate = "2016-04-14T10:44:00+0000"

let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ssZ"
dateFormatter.locale = Locale(identifier: "en_US_POSIX") // set locale to reliable US_POSIX
let date = dateFormatter.date(from:isoDate)!

Get the date components for year, month, day and hour from the date

let calendar = Calendar.current
let components = calendar.dateComponents([.year, .month, .day, .hour], from: date)

Finally create a new Date object and strip minutes and seconds
```
let finalDate = calendar.date(from:components)
```

Consider also the convenience formatter ISO8601DateFormatter introduced in iOS 10 / macOS 12:

let isoDate = "2016-04-14T10:44:00+0000"

let dateFormatter = ISO8601DateFormatter()
let date = dateFormatter.date(from:isoDate)!

回答2:

Try the following date Format.

let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy'-'MM'-'dd'T'HH':'mm':'ssZZZ"
let date = dateFormatter. dateFromString (strDate)

Hope it helps..

Swift 4.1 :

let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy'-'MM'-'dd'T'HH':'mm':'ssZZZ"
let date = dateFormatter.date(from: strDate)

回答3:

In Swift 4.1 you can do:

func getDate() -> Date? {
    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss"
    dateFormatter.timeZone = TimeZone.current
    dateFormatter.locale = Locale.current
    return dateFormatter.date(from: "2015-04-01T11:42:00") // replace Date String
}

回答4:

Swift 3.0 - 4.2

import Foundation

extension String {

    func toDate(withFormat format: String = "yyyy-MM-dd HH:mm:ss")-> Date?{

        let dateFormatter = DateFormatter()
        dateFormatter.timeZone = TimeZone(identifier: "Asia/Tehran")
        dateFormatter.locale = Locale(identifier: "fa-IR")
        dateFormatter.calendar = Calendar(identifier: .gregorian)
        dateFormatter.dateFormat = format
        let date = dateFormatter.date(from: self)

        return date

    }
}

extension Date {

    func toString(withFormat format: String = "EEEE ، d MMMM yyyy") -> String {

        let dateFormatter = DateFormatter()
        dateFormatter.locale = Locale(identifier: "fa-IR")
        dateFormatter.timeZone = TimeZone(identifier: "Asia/Tehran")
        dateFormatter.calendar = Calendar(identifier: .persian)
        dateFormatter.dateFormat = format
        let str = dateFormatter.string(from: self)

        return str
    }
}

回答5:

Hi You have separate T Format and then convert as you like

// create dateFormatter with UTC time format
let dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd'T'HH:mm:ss"
dateFormatter.timeZone = NSTimeZone(name: "UTC")
let date = dateFormatter.dateFromString("2015-04-01T11:42:00")

// change to a readable time format and change to local time zone
dateFormatter.dateFormat = "EEE, MMM d, yyyy - h:mm a"
dateFormatter.timeZone = NSTimeZone.localTimeZone() 
let timeStamp = dateFormatter.stringFromDate(date!)

回答6:

Just your passing your dateformate and your date then you get Year,month,day,hour. Extra info

func GetOnlyDateMonthYearFromFullDate(currentDateFormate:NSString , conVertFormate:NSString , convertDate:NSString ) -> NSString
    {
        let dateFormatter = NSDateFormatter()
        dateFormatter.dateFormat = currentDateFormate as String
        let formatter = NSDateFormatter()
        formatter.dateFormat = Key_DATE_FORMATE as String
        let finalDate = formatter.dateFromString(convertDate as String)
        formatter.dateFormat = conVertFormate as String
        let dateString = formatter.stringFromDate(finalDate!)

        return dateString
    }

Get Year

let Year = self.GetOnlyDateMonthYearFromFullDate("yyyy-MM-dd'T'HH:mm:ssZ", conVertFormate: "YYYY", convertDate: "2016-04-14T10:44:00+0000") as String

Get Month

let month = self.GetOnlyDateMonthYearFromFullDate("yyyy-MM-dd'T'HH:mm:ssZ", conVertFormate: "MM", convertDate: "2016-04-14T10:44:00+0000") as String

Get Day

let day = self.GetOnlyDateMonthYearFromFullDate("yyyy-MM-dd'T'HH:mm:ssZ", conVertFormate: "dd", convertDate: "2016-04-14T10:44:00+0000") as String

Get Hour

let hour  = self.GetOnlyDateMonthYearFromFullDate("yyyy-MM-dd'T'HH:mm:ssZ", conVertFormate: "hh", convertDate: "2016-04-14T10:44:00+0000") as String

回答7:

In swift4,

    var Msg_Date_ = "2019-03-30T05:30:00+0000"

    let dateFormatterGet = DateFormatter()
    dateFormatterGet.dateFormat = "yyyy-MM-dd'T'HH:mm:ss"
    let dateFormatterPrint = DateFormatter()
    dateFormatterPrint.dateFormat = "MMM dd yyyy h:mm a"  //"MMM d, h:mm a" for  Sep 12, 2:11 PM
    let datee = dateFormatterGet.date(from: Msg_Date_)
    Msg_Date_ =  dateFormatterPrint.string(from: datee ?? Date())

    print(Msg_Date_)

//output :- Mar 30 2019 05:30 PM

回答8:

Please use an ISO8601 parsing library for doing this. There are too many ways how the string could be encoded. Don't rely on a specific format and don't rely on the server sending always the same. The problems start with the 'Z' at the end and it will extend through all varieties of the standard. A parsing library will handle all cases and will always provide a safe conversion - whereas a fixed formatting string is likely to fail in the future.

You could use one of these libraries. They are also available on CococaPods:

https://github.com/boredzo/iso-8601-date-formatter/

https://github.com/malcommac/SwiftDate

Take a look at the implementations. They are both several hundred lines long - for good reason.

With regards to the question: You can pull out the date components from the date using NSDateComponents. The example on the website covers exactly your case.

https://developer.apple.com/documentation/foundation/nscalendar/1414841-components?language=objc

Please be aware, that converting your date will take into account the time zone. You might want to set the 'locale' of the NSCalendar explicitly.

回答9:

just Step 1 > get the String value from JSON or dataSource

Step 2 > create a local variable and assign it.

let startDate = CurrentDashBoard.startdate

Step 3> create an instance of DateFormatter.

let dateFormatter = DateFormatter()

step 4> call the dateFormat from dateFormatter and provide saved date dataType.

dateFormatter.dateFormat = "MM-dd-yyyy HH:mm:ss"("may be String formate")

step 5> Assign the Local variable to this variable to convert.

let dateFromStringstartDate : NSDate = dateFormatter.date(from: startDate)! as NSDate

Step 6> provide your required date Formate by the following code.

dateFormatter.dateFormat = "MM/dd/yyyy HH:mm:ss"

Step 6> Assign it to label/text

cell.lblStartDate.text = String(format: "%@", strstartDate)

Code:

let startDate = CurrentDashBoard.startdate let dateFormatter = DateFormatter() 
dateFormatter.dateFormat = "MM-dd-yyyy HH:mm:ss" let dateFromStringstartDate : 
NSDate = dateFormatter.date(from: startDate)! as NSDate
dateFormatter.dateFormat = "MM/dd/yyyy HH:mm:ss"
let strstartDate = dateFormatter.string(from: dateFromStringstartDate as Date)

来源：https://stackoverflow.com/questions/36861732/convert-string-to-date-in-swift

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swift

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