I have a Json Data which contains 2 Key:Value "startDate":"2008.11", and "endDate":"2011.10", respectively, and what i wanna do is to loop through the date range until this statement becomes false:
while startDate <= endDate {
let range += startDate + 1
print(range)
}
something similar like this.. .
how to loop through the date range in swift?
Assuming you have extracted the json values you can use DateComponents to calculate the number of months between the values
let startDate = "2008.11".split(separator: ".").compactMap {Int($0)}
let endDate = "2011.10".split(separator: ".").compactMap {Int($0)}
//Maybe add a check here that both arrays are of length 2
let startComponents = DateComponents(year: startDate[0], month: startDate[1])
let endComponents = DateComponents(year: endDate[0], month: endDate[1])
let months = Calendar.current.dateComponents([.month], from: startComponents, to: endComponents).month!
And now you can use a simple for loop
for n in 0..<months {
//...
}
If you want to work with days (and dates) you can calculate them as
let days = Calendar.current.dateComponents([.day], from: startComponents, to: endComponents).day!
but you need to decide what day in month to use for startDate and endDate
Related
How can I get the date of previous month matching specified day ? in Swift
if I have this function getPreviousMonthDate(matchingDay day: Int) -> Date
Examples:
following (dd/mm/yyyy)
If Today is 25/07/2022 and I call getPreviousMonthDate(matchingDay: 27)
: return value would be 27/06/2022 .
If Today is 18/04/2022 and I call getPreviousMonthDate(matchingDay: 14)
: return value would be 14/03/2022 .
If Today is 15/01/2022 and I call getPreviousMonthDate(matchingDay: 16)
: return value would be 16/12/2021 .
and so on...
You can use date components as following:
func getPreviousMonthDate(matchingDay day: Int) -> Date {
let calendar = Calendar.current
let comps = calendar.dateComponents([.year, .month, .day], from: Date())
var comps2 = DateComponents()
comps2.year = comps.year
comps2.month = comps.month! - 1
comps2.day = day
return calendar.date(from: comps2)!
}
I force-unwrapped the date to match your function declaration, I suggest that you deal with the optional dates properly though.
I am having a small issue with getting the total days in a month using Swift.
I have extended the Date class and created this function:
func daysInMonth() -> Int {
print(self.day) ##30
print(self.month) ##12
print(self) ## 2021-11-30 23:46:29 +0000
print(Calendar.current.range(of: .day, in: .month, for: self)?.count) ##31
return Calendar.current.range(of: .day, in: .month, for: self)?.count ?? 0
}
I have set the Date&Time to the 30th of November, at 11:45 PM in the settings of my Mac, in Preferences.
I called the above function at 11:46 PM and obtained the above results (inline, next to the print statements).
The date output is correct as well as the day. The month output is wrong and the result is 31 days in the month of November.
If I run this exact same code before 10:00 PM, I get the right result which is 30 days.
Does anyone know why this is happening?
Thank you,
Paprika
It's a GMT offset issue combined with the current day in a month.
When you create a date without set a day, it will be set to the first day of the month.
So, if your timezone offset is for example -4 means your are 4 hours behind the GMT 0 and by default the timezone defined at Calendar.current is equal the system timezone. So what it means? Means you'll obtain the previous month if you test it in a boundary of 23 + (-4) or the next month if your offset is positive.
You can test this behaviour copying'n paste the following code in the Playground.
func getDaysInMonth(month: Int, year: Int, offset: Int = 0) -> Int? {
let someDate = DateComponents(year: year, month: month, hour: 3)
var current = Calendar.current
let timezone = TimeZone(secondsFromGMT: 60 * 60 * offset)!
current.timeZone = timezone
guard let someDay = current.date(from: someDate) else { return nil }
print("date: \(someDay)") // this will always
return someDay.daysInCurrentMonth
}
for hour in -12...12 {
print("hour: \(hour)\ndays: \(getDaysInMonth(month: 10, year: 2021, offset: hour) ?? -1)")
print("---\n")
}
extension Date {
var daysInCurrentMonth: Int? {
Calendar.current.range(of: .day, in: .month, for: self)?.count
}
}
Notice the days will change starting by your current system time zone (notice only the month will change).
How to fix this?
In your case, I guess you just want to show how many days a month have, so you can just set the to zero like this:
TimeZone(secondsFromGMT: 0)
Do this change at a instance of Calendar.current and check if it works for you.
It appears there something wrong with your Date extension methods for .day and .month.
Without seeing code it's hard to determine what the problem is though. Below is some code for returning the current month (Int) and current numbered day of month (Int)
extension Date
{
var month: Int
{
let date = Date()
let calendar = Calendar.current
let components = calendar.dateComponents([.month], from: date)
return components.month
}
var day: Int
{
let date = Date()
let calendar = Calendar.current
let components = calendar.dateComponents([.day], from: self)
return components.day
}
}
Please also ensure your time/date settings are correct on your mac/simulator/device. If these are wrong - it could have been jumping to a different month if you were in a timezone that was ahead a few hours.
I am using Swift 3, and i would like to print the every day between two dates.
For example:
08-10-2017 -> Start Date
08-15-2017 -> End Date
Should print:
08-10-2017
08-11-2017
08-12-2017
08-13-2017
08-14-2017
08-15-2017
I want to get ranges in two specific date, can someone help me out please. I tried to put these two dates to for loop but no chance.
You need to create a calendar based dates, and start increasing start date until you reach end date. Here is a code snippet, how to do it:
func showRange(between startDate: Date, and endDate: Date) {
// Make sure startDate is smaller, than endDate
guard startDate < endDate else { return }
// Get the current calendar, i think in your case it should some fscalendar instance
let calendar = Calendar.current
// Calculate the endDate for your current calendar
let calendarEndDate = calendar.startOfDay(for: endDate)
// Lets create a variable, what we can increase day by day
var currentDate = calendar.startOfDay(for: startDate)
// Run a loop until we reach the end date
while(currentDate <= calendarEndDate) {
// Print the current date
print(currentDate)
// Add one day at the time
currentDate = Calendar.current.date(byAdding: .day, value: 1, to: currentDate)!
}
}
Usage:
let today = Date()
let tenDaysLater = Calendar.current.date(byAdding: .day, value: 10, to: today)!
showRange(between: today, and: tenDaysLater)
I have a date in string format, example:- "2017-07-31" or can be multiple dates (any) in string format. My requirement is to check this date to current date and if it is greater than 0 and less than 15, then that time I have to do another operation.
So first I am converting that date string to in date format. But it is giving one day ago date. Here is my code:
//Date from string
func dateFromString(date : String) -> Date {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd"
let currentDate = (dateFormatter.date(from: date))//(from: date))
return currentDate!
}
Ex. my date is "2017-08-30" and this function is returning 2017-08-29 18:30:00 +0000 in date format. It means 1 day ago. I am little bit confuse about dates operation. I read so many blogs also.
After that I have to check this date to current date if it is in between 0 < 15 than I will do other operation.
Comparing two dates:
extension Date {
func daysBetweenDate(toDate: Date) -> Int {
let components = Calendar.current.dateComponents([.day], from: self, to: toDate)
return components.day ?? 0
}
}
If my date is today date and comparing to tomorrow date then also it is giving 0 days difference. Why?
If – for example – the current date is 2017-07-31 at 11AM then the
difference to 2017-08-01 (midnight) is 0 days and 13 hours, and that's
why you get "0 days difference" as result.
What you probably want is to compare the difference between the start
of the current day and the other date in days:
extension Date {
func daysBetween(toDate: Date) -> Int {
let cal = Calendar.current
let startOfToday = cal.startOfDay(for: self)
let startOfOtherDay = cal.startOfDay(for: toDate)
return cal.dateComponents([.day], from: startOfToday, to: startOfOtherDay).day!
}
}
Try this method for convert string to date:
func dateFromString(date : String) -> Date {
let dateFormatter = DateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd"
dateFormatter.timeZone = TimeZone.init(abbreviation: "UTC")
let currentDate = (dateFormatter.date(from: date))//(from: date))
return currentDate!
}
Try this to compare the time between two dates in seconds :
var seconds = Calendar.current.dateComponents([.second], from: date1!, to: date2!).second ?? 0
seconds = abs(seconds)
let min = seconds/60 // this gives you the number of minutes between two dates
let hours = seconds/3600 // this gives you the number of hours between two dates
let days = seconds/3600*24 // this gives you the number of days between two dates
I have a dictionary like this:
var dic = [NSDate: Int]()
it is used in my iOS to-do app to get the number of finished tasks of a particular date. I only care about the year, month and day sections in NSDate and also want to be able to get the number of tasks in a particular date using this dictionary, how can I do that? thanks.
Instead of storing your date as NSDate in your dictionary you can save it as String so that comparison will be easier. Use following code to store it as a string
func dateFromString(date : NSDate) -> String {
var dateFormatter = NSDateFormatter()
dateFormatter.dateFormat = "yyyy-MM-dd"
return dateFormatter.stringFromDate(date)
}
You can pass NSDate() to above function and it will give you string containing only year, month and date. For retrieving your data from dictionary use following.
func dateFrom(year:Int, month:Int, day:Int) -> String {
let components = NSDateComponents()
components.year = year
components.month = month
components.day = day
let gregorian = NSCalendar(identifier:NSCalendarIdentifierGregorian)
let date = gregorian!.dateFromComponents(components)
return dateFromString(date!)
}
You can pass year, month and date to above function and it will return corresponding date in string format. So your dictionary operations will look like
dict[dateFromString(NSDate())] = 1 //for insertion or updation
let numOfTasks = dict[dateFrom(2016, month: 1, day: 15)] //to get task for any particular day
EDIT
If you want to proceed with NSDate as key for your dictionary then you'll have to modify above code as follows. dateFrom will return date with year,month and date of your choice, and time will be some constant value. Time will be set to midnight in your current time zone if you don't set it.
func dateFrom(year:Int, month:Int, day:Int) -> NSDate {
let components = NSDateComponents()
components.year = year
components.month = month
components.day = day
let gregorian = NSCalendar(identifier:NSCalendarIdentifierGregorian)
let date = gregorian!.dateFromComponents(components)
return date!
}
And for getting current date use following so that you store date object with current year, date, month and time to some constant value.
func getCurrentDate()->NSDate {
let date = NSDate()
let calendar = NSCalendar.currentCalendar()
let components = calendar.components([.Day , .Month , .Year], fromDate: date)
return dateFrom(components.year, month: components.month, day: components.day)
}
Usage will be as follows
dict[getCurrentDate()] = i //for insertion or updation
let numOfTasks = dict[dateFrom(2016, month: 1, day: 15)] //to get task for any particular day