Get firstdate, lastdate of month?

Question

I want to get firstdate、lastdate of month，I try

NSDateComponents *components = [calendar components:units fromDate:[NSDate date]];
[components setDay:1];
self.c         


        

Answer 1

Looks like there is no need for any tricks or hacks, NSCalendar's rangeOfUnit does the job pretty nicely:

NSCalendar *cal = [NSCalendar currentCalendar];

NSDateComponents *dc = [[NSDateComponents alloc] init];
dc.year = 1947;
dc.month = 8; //desired month

//calculate start date
dc.day = 1; //As far as I can think start date of a month will always be 1
NSDate *start = [cal dateFromComponents:dc];

//calculate last date of month
NSRange dim = [cal rangeOfUnit:NSCalendarUnitDay inUnit:NSCalendarUnitMonth forDate:start]; // we used start date as it has the same month & year value as desired
dc.day=dim.length; //this is the simply the last day of the desired month
NSDate *last = [[NSCalendar currentCalendar] dateFromComponents:dc];

Log the values for verification:

NSLog(@"Start day of month Date: %@", start);
NSLog(@"Last day of month Date: %@", last);

Apple docs on NSCalendar rangeOfUnit: https://developer.apple.com/documentation/foundation/nscalendar/1418344-rangeofunit

p.s looks like this uses the same logic as @Scott Means's answer, but doesn't require any category, so use which ever answer you prefer!