Difference between two NSDates in Months and Years in Swift iOS - ios

Question

I have to calculate the time between two NSDates in Month + Year.
Example 1:
Start Date: September 2018
End Date: May 2019
So I have to get the difference between these two dates and have to display only last 6 months like below:
April 2019
March 2019
February 2019
January 2019
December 2018
November 2018
Example 2:
Start Date: October 2019
End Date: December 2019
Output should be:
November 2019
October 2019
I can able to to get the difference between two dates in months using below code:
let components = Calendar.current.dateComponents([.weekOfYear, .month], from: subscriptionDate!, to: currentDate!)
Can anyone please help me on this?
Thank you!

Answer 1

You can do this in following way...
//set start & end date in correct format
let strStartDate = "September 2019"
let strEndDate = "December 2019"
//create date formatter
let formatter = DateFormatter()
formatter.dateFormat = "MMMM yyyy"
//convert string into date object
guard let startDate = formatter.date(from: strStartDate) else {
print("invalid start date")
return
}
//convert string into date object
guard let endDate = formatter.date(from: strEndDate) else {
print("invalid end date time")
return
}
//calculate the month from end date and that should not exceed the start date
for month in 1...6 {
if let dt = Calendar.current.date(byAdding: .month, value: -month, to: endDate) {
if dt.compare(startDate) == .orderedAscending {
break
}
print(formatter.string(from: dt!))
}
}

Answer 2

Here's a way to do this:
func monthsBetween(start: DateComponents, end: DateComponents) -> [String] {
let monthsCount = Calendar.current.dateComponents([.month], from: start, to: end).month! - 1
guard monthsCount > 0 else { return [] }
return (1...monthsCount).map {
var monthYear = start
monthYear.month! += $0
let date = Calendar.current.date(from: monthYear)!
let formatter = DateFormatter()
formatter.dateFormat = "MMMM yyyy"
return formatter.string(from: date)
}
}
You should pass in DateComponents with only the month and year components into this method. You can get a DateComponents object with only the month and year from a Date like this.
Calendar.current.dateComponents([.month, .year], from: someDate)