How to get 18-digit current timestamp in Swift?

问题:

I want to get current timestamp like this:

636110767775716756​

However, when I do :

NSDate().timeIntervalSince1970

It returns a value like this:

1475491615.71278

How do I access current time stamp ticks in the format I want? I check the dates from here:

回答1:

You seem be looking for what DateTime.Ticks is in C#, i.e. the time since 0001-01-01 measured in 100-nanosecond intervals.

The code from your provided link Swift: convert NSDate to c# ticks can be translated to Swift easily:

// Swift 2:
extension NSDate {
    var ticks: UInt64 {
        return UInt64((self.timeIntervalSince1970 + 62_135_596_800) * 10_000_000)
    }
}

// Swift 3:
extension Date {
    var ticks: UInt64 {
        return UInt64((self.timeIntervalSince1970 + 62_135_596_800) * 10_000_000)
    }
}

Example (Swift 3):

let ticks = Date().ticks
print(ticks) // 636110903202288256

or as a string:

let sticks = String(Date().ticks)
print(sticks)

And while are are at it, the reverse conversion from ticks to Date would be

// Swift 2:
extension NSDate {
    convenience init(ticks: UInt64) {
        self.init(timeIntervalSince1970: Double(ticks)/10_000_000 - 62_135_596_800)
    }
}

// Swift 3:
extension Date {
    init(ticks: UInt64) {
        self.init(timeIntervalSince1970: Double(ticks)/10_000_000 - 62_135_596_800)
    }
}

Example (Swift 3):

let date = Date(ticks: 636110903202288256)

回答2:

Here is a solution that I find very elegant. I extended NSDate (although it's just Date now in Swift 3) to include a toMillis() func which will give you the Int64 value of the date object that you're working with.

extension Date {
    func toMillis() -> Int64! {
        return Int64(self.timeIntervalSince1970 * 1000)
    }
}

Usage:

let currentTimeStamp = Date().toMillis()

Cheers

回答3:

In Swift:

if you want to makeit as global variable see below code:

var Timestamp: String {
   return "\(NSDate().timeIntervalSince1970 * 1000)"
}

Then, you can call it

println("Timestamp: \(Timestamp)")

The *1000 is for miliseconds, if you'd prefer, you can remove that. If keep it as an NSTimeInterval.

var Timestamp: NSTimeInterval {
    return NSDate().timeIntervalSince1970 * 1000
}

In Objective C:

If your want to declare as symbolic constant see below code:

#define TimeStamp [NSString stringWithFormat:@"%f",[[NSDate date] timeIntervalSince1970] * 1000]

Then Call it like this:

NSString * timestamp = TimeStamp;

Or create a global method:

- (NSString *) timeStamp {
    return [NSString stringWithFormat:@"%f",[[NSDate date] timeIntervalSince1970] * 1000];
}

Have a Note: The 1000 is to convert the timestamp to milliseconds. You can remove this if you prefer your timeInterval in seconds.