How do I find the number of days in given month and year using swift

I want to find the total number days on given month and year. Example: I want to find total number of days on year = 2015, month = 7

Solution 1:

First create an NSDate for the given year and month:

let dateComponents = NSDateComponents()
dateComponents.year = 2015
dateComponents.month = 7

let calendar = NSCalendar.currentCalendar()
let date = calendar.dateFromComponents(dateComponents)!

Then use the rangeOfUnit() method, as described in Number of days in the current month using iPhone SDK?:

// Swift 2:
let range = calendar.rangeOfUnit(.Day, inUnit: .Month, forDate: date)
// Swift 1.2:
let range = calendar.rangeOfUnit(.CalendarUnitDay, inUnit: .CalendarUnitMonth, forDate: date)

let numDays = range.length
print(numDays) // 31

Update for Swift 3 (Xcode 8):

let dateComponents = DateComponents(year: 2015, month: 7)
let calendar = Calendar.current
let date = calendar.date(from: dateComponents)!

let range = calendar.range(of: .day, in: .month, for: date)!
let numDays = range.count
print(numDays) // 31

Solution 2:

Updated for Swift 3.1, Xcode 8+, iOS 10+

let calendar = Calendar.current
let date = Date()

// Calculate start and end of the current year (or month with `.month`):
let interval = calendar.dateInterval(of: .year, for: date)! //change year it will no of days in a year , change it to month it will give no of days in a current month

// Compute difference in days:
let days = calendar.dateComponents([.day], from: interval.start, to: interval.end).day!
print(days)

Solution 3:

In extension format, using self to be able to return the number of days more dynamically (Swift 3).

extension Date {

func getDaysInMonth() -> Int{
    let calendar = Calendar.current

    let dateComponents = DateComponents(year: calendar.component(.year, from: self), month: calendar.component(.month, from: self))
    let date = calendar.date(from: dateComponents)!

    let range = calendar.range(of: .day, in: .month, for: date)!
    let numDays = range.count

    return numDays
}

}

Solution 4:

Swift 5.0

func getDaysInMonth(month: Int, year: Int) -> Int? {
        let calendar = Calendar.current

        var startComps = DateComponents()
        startComps.day = 1
        startComps.month = month
        startComps.year = year

        var endComps = DateComponents()
        endComps.day = 1
        endComps.month = month == 12 ? 1 : month + 1
        endComps.year = month == 12 ? year + 1 : year

        
        let startDate = calendar.date(from: startComps)!
        let endDate = calendar.date(from:endComps)!

        
        let diff = calendar.dateComponents([Calendar.Component.day], from: startDate, to: endDate)

        return diff.day
    }
    if let numberOfDays = getDaysInMonth(month: 1, year: 2015) {
     print(numberOfDays)

     }

Swift 2.0

func getDaysInMonth(month: Int, year: Int) -> Int
{
    let calendar = NSCalendar.currentCalendar()

    let startComps = NSDateComponents()
    startComps.day = 1
    startComps.month = month
    startComps.year = year

    let endComps = NSDateComponents()
    endComps.day = 1
    endComps.month = month == 12 ? 1 : month + 1
    endComps.year = month == 12 ? year + 1 : year

    let startDate = calendar.dateFromComponents(startComps)!
    let endDate = calendar.dateFromComponents(endComps)!

    let diff = calendar.components(NSCalendarUnit.Day, fromDate: startDate, toDate: endDate, options: NSCalendarOptions.MatchFirst)

    return diff.day
}

let days = getDaysInMonth(4, year: 2015) // April 2015 has 30 days
print(days) // Prints 30

Swift 1.2

func getDaysInMonth(month: Int, year: Int) -> Int
{
    let calendar = NSCalendar.currentCalendar()

    let startComps = NSDateComponents()
    startComps.day = 1
    startComps.month = month
    startComps.year = year

    let endComps = NSDateComponents()
    endComps.day = 1
    endComps.month = month == 12 ? 1 : month + 1
    endComps.year = month == 12 ? year + 1 : year

    let startDate = calendar.dateFromComponents(startComps)!
    let endDate = calendar.dateFromComponents(endComps)!

    let diff = calendar.components(NSCalendarUnit.CalendarUnitDay, fromDate: startDate, toDate: endDate, options: NSCalendarOptions.allZeros)

    return diff.day
}

let days = getDaysInMonth(4, 2015) // There were 30 days in April 2015
println(days) // Prints 30