iPhone 날짜 관련 함수 모음

1. NSString to NSDate

NSDateFormatter *df = [[NSDateFormatter alloc] init];

[df setDateFormat:@"yyyy-MM-dd hh:mm:ss a"];

NSDate *myDate = [df dateFromString: myDateAsAStringValue];


2. NSDate to NSDateComponents

NSCalendar *calendar = [NSCalendar currentCalendar];

unsigned int unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;

NSDateComponents *c = [calendar components:unitFlags fromDate:[NSDate date]];  


3. NSDate to NSString

NSDateFormatter *formatter = [[NSDateFormatter alloc] init];

[formatter setDateFormat:@"yyyy"];

//Optionally for time zone converstions

[formatter setTimeZone:[NSTimeZone timeZoneWithName:@"..."]];

NSString *stringFromDate = [formatter stringFromDate:myNSDateInstance];