DateFormatter showing different date

Question

I am new to iOS and I want to add some milliseconds say (5) to my date. I have used the below code but I am not getting the exact date which I am using

let str_TimeStamp = "2017-08-09 10:26:30.8"
let formatter = DateFormatter()
formatter.dateFormat = "yyyy-MM-dd HH:mm:ss.S"
formatter.timeZone = NSTimeZone(abbreviation: "UTC")! as TimeZone

var dateInput: Date? = formatter.date(from: str_TimeStamp)
dateInput = dateInput?.addingTimeInterval(TimeInterval(5*100))
let endtime = formatter.string(from: dateInput!)
print(endtime)

I am getting the output having some delay of mins

2017-08-09 10:28:10.8

Answer 1

The parameter of the addingTimeInterval is the value to add, in seconds.

So, addingTimeInterval(TimeInterval(5*100)) - adds 500 seconds = 8 minutes.

If you want to add some milliseconds say (5), you should add this time interval: 0.005

So, the final code is:

let str_TimeStamp = "2017-08-09 10:26:30.8"
let formatter = DateFormatter()
formatter.dateFormat = "yyyy-MM-dd HH:mm:ss.SSSS"
formatter.timeZone = TimeZone(abbreviation: "UTC")

var dateInput = formatter.date(from: str_TimeStamp)
dateInput = dateInput?.addingTimeInterval(5/1000)

if let dateInput = dateInput {
    let endtime = formatter.string(from: dateInput)
    print(endtime) // prints 2017-08-09 10:26:30.8050
}