dateformat spelling format swift - swift

Question

I am removing the current time from the current time and trying to find the minute difference. But it says 10/09/2019 13:13 and there is an error in the extraction process (I want to print as 1313) .1313 I can perform the extraction process. How do I print this data the way I want? I want to print dateFormat = "HHmm". In timertext2New.text, dateFormat = "dd / MM / yyyy HH: mm" like this. But I want to save it in HHmm format.
save12 output: 05/09/2019 10:48 but I want it to be "1048" . To perform extraction.
let formatter = DateFormatter()
formatter.dateFormat = "dd/MM/yyyy HH:mm"
timertext2New.text = formatter.string(from: datePicker.date)
let timehafıza2 = String(self.timertext2New.text!)
let df2 = DateFormatter()
df2.dateFormat = "HHmm"
var str2 = df2.string(from: Date())
str2 = timehafıza2
UserDefaults.standard.setValue(str2, forKey: "timertext2")
override func viewDidLoad() {
super.viewDidLoad()
let date = Date()
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "HHmm"
let hour = dateFormatter.string(from: date)
var save12 = UserDefaults.standard.integer(forKey: "timertext2")
var fark : Int = (Int(hour)! - Int(save12))
}

Answer 1

Your code is pretty confusing and cannot work
You convert a date from a date picker with format "dd/MM/yyyy HH:mm"
Then you create a string with format "HHmm" from the current date which will be destroyed immediately because
You overwrite this string with the dd/MM/yyyy HH:mm string and save it to UserDefaults
Later you read the value from UserDefaults as integer which returns 0 because the "dd/MM/yyyy HH:mm" format is not representable by an integer.
My suggestion is to save all dates as Date and perform the date math with the dedicated methods of Calendar