Get an upcoming date between two date iOS swift

Problem:

I had two date with me fromdate and todate.I want to get the upcoming date(greater than today date).

Solution:

   
    func getUpcomingDate(fromDate: NSDate, toDate: NSDate)-> String{
        var fromDatet = fromDate
       
        repeat {
                      
            if fromDatet.isGreaterThanDate(dateToCompare: NSDate()){       
                    return dateStr
            }
            fromDatet = fromDatet.addDays(daysToAdd: 1)
        } while (fromDatet.isLessThanDate(dateToCompare: toDate) || fromDatet.isEqual(to: toDate as Date))
       
        return ""
    }

//adding the days to the date
func addDays(daysToAdd: Int) -> NSDate {
        let secondsInDays: TimeInterval = Double(daysToAdd) * 60 * 60 * 24
        let dateWithDaysAdded: NSDate = self.addingTimeInterval(secondsInDays)
       
        //Return Result
        return dateWithDaysAdded
    }


//check if less than date
func isLessThanDate(dateToCompare: NSDate) -> Bool {
        //Declare Variables
        var isLess = false
       
        //Compare Values
        if NSDate().compare(dateToCompare as Date) == ComparisonResult.orderedAscending {
            isLess = true
        }
       
        //Return Result
        return isLess
    }