"Date operation for iOS class extensions" Nsdate+helpers

Import "Date.h"

@implementation NSDate (Helpers)

Get Date: 19871127.
-(NSString *) getformatyearmonthday
{
NSString *string = [NSString stringwithformat:@ "%d%02d%02d", [Self getyear],[self getmonth],[self GetDay]];
return string;
}

The date is the week ordinal of the year
-(int) getweekofyear
{
int i;
int year = [self getYear];
NSDate *date = [self endofweek];
for (i = 1;[ [Date dateafterday:-7 * i] getYear] = = year;i++)
{
}
return i;
}
Date of day days (if days is negative, the date before |day|)
-(NSDate *) Dateafterday: (int) Day
{
Nscalendar *calendar = [Nscalendar Currentcalendar];
Get the weekday component of the current date
nsdatecomponents *weekdaycomponents = [Calendar Components:nsweekdaycalendarunit fromdate:self];
Nsdatecomponents *componentstoadd = [[Nsdatecomponents alloc] init];
To get the end of week for a particular date, add (7-weekday) days
[Componentstoadd Setday:day];
NSDate *dateafterday = [Calendar Datebyaddingcomponents:componentstoadd todate:self options:0];
[Componentstoadd release];

return dateAfterDay;

}
Date months after month
-(NSDate *) Dateaftermonth: (int) Month
{
Nscalendar *calendar = [Nscalendar Currentcalendar];
Nsdatecomponents *componentstoadd = [[Nsdatecomponents alloc] init];
[Componentstoadd Setmonth:month];
NSDate *dateaftermonth = [Calendar Datebyaddingcomponents:componentstoadd todate:self options:0];
[Componentstoadd release];

return dateAfterMonth;

}
Get Day
-(Nsuinteger) getday{
Nscalendar *calendar = [Nscalendar Currentcalendar];
nsdatecomponents *daycomponents = [Calendar components: (Nsdaycalendarunit) fromdate:self];
return [daycomponents Day];
}
Get month
-(Nsuinteger) GetMonth
{
Nscalendar *calendar = [Nscalendar Currentcalendar];
nsdatecomponents *daycomponents = [Calendar components: (Nsmonthcalendarunit) fromdate:self];
return [daycomponents month];
}
Get year
-(Nsuinteger) getYear
{
Nscalendar *calendar = [Nscalendar Currentcalendar];
nsdatecomponents *daycomponents = [Calendar components: (Nsyearcalendarunit) fromdate:self];
return [daycomponents year];
}
Get hours
-(int) Gethour {
Nscalendar *calendar = [Nscalendar Currentcalendar];
Nsuinteger Unitflags =nsyearcalendarunit| Nsmonthcalendarunit | Nsdaycalendarunit | Nshourcalendarunit| Nsminutecalendarunit;
nsdatecomponents *components = [Calendar components:unitflags fromdate:self];
Nsinteger hour = [Components hour];
return (int) hour;
}
Get minutes
-(int) Getminute {
Nscalendar *calendar = [Nscalendar Currentcalendar];
Nsuinteger Unitflags =nsyearcalendarunit| Nsmonthcalendarunit | Nsdaycalendarunit | Nshourcalendarunit| Nsminutecalendarunit;
nsdatecomponents *components = [Calendar components:unitflags fromdate:self];
Nsinteger minute = [Components minute];
return (int) minute;
}
-(int) Gethour: (NSDate *) Date {
Nscalendar *calendar = [Nscalendar Currentcalendar];
Nsuinteger Unitflags =nsyearcalendarunit| Nsmonthcalendarunit | Nsdaycalendarunit | Nshourcalendarunit| Nsminutecalendarunit;
nsdatecomponents *components = [Calendar components:unitflags fromdate:date];
Nsinteger hour = [Components hour];
return (int) hour;
}
-(int) Getminute: (NSDate *) Date {
Nscalendar *calendar = [Nscalendar Currentcalendar];
Nsuinteger Unitflags =nsyearcalendarunit| Nsmonthcalendarunit | Nsdaycalendarunit | Nshourcalendarunit| Nsminutecalendarunit;
nsdatecomponents *components = [Calendar components:unitflags fromdate:date];
Nsinteger minute = [Components minute];
return (int) minute;
}
Days before the current date
-(Nsuinteger) Daysago {
Nscalendar *calendar = [Nscalendar Currentcalendar];
nsdatecomponents *components = [Calendar components: (Nsdaycalendarunit)
Fromdate:self
Todate:[nsdate Date]
OPTIONS:0];
return [Components day];
}
Midnight time is a few days from now
-(Nsuinteger) Daysagoagainstmidnight {
Get a midnight version of ourself:
NSDateFormatter *mdf = [[NSDateFormatter alloc] init];
[MDF setdateformat:@ "YYYY-MM-DD"];
NSDate *midnight = [mdf datefromstring:[mdf stringfromdate:self];
[MDF release];

return (int)[midnight timeIntervalSinceNow] / (60*60*24) *-1;

}

• (NSString *) Stringdaysago {
  return [self stringdaysagoagainstmidnight:yes];
  }

• (NSString *) Stringdaysagoagainstmidnight: (BOOL) Flag {
  Nsuinteger Daysago = (flag)? [Self daysagoagainstmidnight]: [Self daysago];
  NSString *text = nil;
  Switch (Daysago) {
  Case 0:
  Text = @ "Today";
  Break
  Case 1:
  Text = @ "Yesterday";
  Break
  Default
  Text = [NSString stringwithformat:@ "%d days ago", Daysago];
  }
  return text;
  }

Returns the day ordinal of a week (the first day of the weekend)
-(Nsuinteger) weekday {
Nscalendar *calendar = [Nscalendar Currentcalendar];
nsdatecomponents *weekdaycomponents = [Calendar components: (Nsweekdaycalendarunit) fromdate:self];
return [weekdaycomponents weekday];
}
Convert to NSString type
+ (NSDate ) datefromstring: (NSString ) string {
return [NSDate datefromstring:string withformat:[nsdate dbformatstring];
}

• (NSDate ) datefromstring: (NSString ) String Withformat: (NSString *) format {
  NSDateFormatter *inputformatter = [[NSDateFormatter alloc] init];
  [Inputformatter Setdateformat:format];
  NSDate *date = [Inputformatter datefromstring:string];
  [Inputformatter release];
  return date;
  }

• (NSString ) stringfromdate: (NSDate ) Date Withformat: (NSString *) format {
  return [date Stringwithformat:format];
  }

• (NSString ) stringfromdate: (NSDate ) Date {
  return [date string];
  }

• (NSString ) stringfordisplayfromdate: (NSDate ) Date prefixed: (BOOL) prefixed {
  /*

  • If the date is on today, display 12-hour time with Meridian,
  • If it is within the last 7 days, display weekday name (Friday)
  • If within the calendar year, display as Jan 23
  • else display as Nov 11, 2008
    */

  NSDate *today = [NSDate Date];
  Nscalendar *calendar = [Nscalendar Currentcalendar];
  nsdatecomponents *offsetcomponents = [Calendar components: (Nsyearcalendarunit | Nsmonthcalendarunit | Nsdaycalendarunit)
  Fromdate:today];

  NSDate *midnight = [Calendar datefromcomponents:offsetcomponents];

  NSDateFormatter *displayformatter = [[NSDateFormatter alloc] init];
  NSString *displaystring = nil;

  //Comparing against Midnight
  if ([date compare:midnight] = = nsordereddescending) {
  if (prefixed) {
  [disp Layformatter setdateformat:@ "' at ' h:mm a"]; At 9:00AM
  } else {
  [displayformatter setdateformat:@ "h:mm a"];//AM
  }
  } else {
  //CHEC K If date is within last 7 days
  nsdatecomponents *componentstosubtract = [[Nsdatecomponents alloc] init];
  [Componentstosubtract setday:-7];
  NSDate *lastweek = [Calendar datebyaddingcomponents:componentstosubtract todate:today options:0];
  [Componentstosubtract release];
  if ([date compare:lastweek] = = nsordereddescending) {
  [displayformatter setdateformat:@ "eeee"];//Tuesday
  } else {
  //check if same calendar year
  Nsinteger thisyear = [offsetcomponents year];

      NSDateComponents *dateComponents = [calendar components:(NSYearCalendarUnit | NSMonthCalendarUnit |NSDayCalendarUnit)                                                    fromDate:date];    NSInteger thatYear = [dateComponents year];    if (thatYear >= thisYear) {        [displayFormatter setDateFormat:@"MMM d"];    } else {        [displayFormatter setDateFormat:@"MMM d, yyyy"];    }}if (prefixed) {    NSString *dateFormat = [displayFormatter dateFormat];    NSString *prefix = @"‘on‘ ";    [displayFormatter setDateFormat:[prefix stringByAppendingString:dateFormat]];}

  }

  Use display formatter to return formatted date string
  displaystring = [Displayformatter stringfromdate:date];
  [Displayformatter release];
  return displaystring;
  }

• (NSString ) stringfordisplayfromdate: (NSDate ) Date {
  return [self stringfordisplayfromdate:date prefixed:no];
  }

• (NSString ) stringWithFormat: (NSString ) Format {
  NSDateFormatter *outputformatter = [[NSDateFormatter alloc] init];
  [Outputformatter Setdateformat:format];
  NSString *timestamp_str = [Outputformatter stringfromdate:self];
  [Outputformatter release];
  return timestamp_str;
  }

• (NSString *) string {
  return [self stringwithformat:[nsdate dbformatstring]];
  }

• (NSString *) Stringwithdatestyle: (Nsdateformatterstyle) Datestyle Timestyle: (nsdateformatterstyle) TimeStyle {
  NSDateFormatter *outputformatter = [[NSDateFormatter alloc] init];
  [Outputformatter Setdatestyle:datestyle];
  [Outputformatter Settimestyle:timestyle];
  NSString *outputstring = [Outputformatter stringfromdate:self];
  [Outputformatter release];
  return outputstring;
  }
  Returns the start time of Sunday

• (NSDate *) Beginningofweek {
  Largely borrowed from "Date and time Programming Guide for Cocoa"
  We ' ll use the default calendar and hope

  Nscalendar *calendar = [Nscalendar Currentcalendar];
  NSDate *beginningofweek = nil;
  BOOL OK = [Calendar Rangeofunit:nsweekcalendarunit startdate:&beginningofweek
  Interval:null Fordate:self];
  if (OK) {
  return beginningofweek;
  }

  Couldn ' t calc via range, so try to grab Sunday, assuming Gregorian style
  Get the weekday component of the current date
  nsdatecomponents *weekdaycomponents = [Calendar Components:nsweekdaycalendarunit fromdate:self];

  /*
  Create A date represent the number of days to subtract from the current date.
  The weekday value for Sunday in the Gregorian calendar are 1, so subtract 1 from the number of days to subtract from the DA Te in question. (If today ' s Sunday, subtract 0 days.)
  */
  Nsdatecomponents *componentstosubtract = [[Nsdatecomponents alloc] init];
  [Componentstosubtract setday:0-([weekdaycomponents Weekday]-1)];
  Beginningofweek = nil;
  Beginningofweek = [Calendar datebyaddingcomponents:componentstosubtract todate:self options:0];
  [Componentstosubtract release];

  Normalize to midnight, extract, month, and day, and create a new date from those.
  nsdatecomponents *components = [Calendar components: (Nsyearcalendarunit | Nsmonthcalendarunit | Nsdaycalendarunit)
  Fromdate:beginningofweek];
  return [Calendar datefromcomponents:components];
  }
  Returns the date of the current day.

• (NSDate *) Beginningofday {
  Nscalendar *calendar = [Nscalendar Currentcalendar];
  Get the weekday component of the current date
  nsdatecomponents *components = [Calendar components: (Nsyearcalendarunit | Nsmonthcalendarunit | Nsdaycalendarunit)
  Fromdate:self];
  return [Calendar datefromcomponents:components];
  }
  Returns the first day of the month
• (NSDate *) beginningofmonth
  {
  return [self dateafterday:-[self getDay] + 1];
  }
  The last day of the month
• (NSDate *) endOfMonth
  {
  return [[Self beginningofmonth] dateaftermonth:1] dateafterday:-1];
  }
  Returns the weekend of the current week

• (NSDate *) Endofweek {
  Nscalendar *calendar = [Nscalendar Currentcalendar];
  Get the weekday component of the current date
  nsdatecomponents *weekdaycomponents = [Calendar Components:nsweekdaycalendarunit fromdate:self];
  Nsdatecomponents *componentstoadd = [[Nsdatecomponents alloc] init];
  To get the end of week for a particular date, add (7-weekday) days
  [Componentstoadd Setday: (7-[weekdaycomponents weekday])];
  NSDate *endofweek = [Calendar Datebyaddingcomponents:componentstoadd todate:self options:0];
  [Componentstoadd release];

  return endofweek;
  }

• (NSString *) dateformatstring {
  return @ "YYYY-MM-DD";
  }

• (NSString *) timeformatstring {
  return @ "HH:mm:ss";
  }

• (NSString *) timestampformatstring {
  return @ "Yyyy-mm-dd HH:mm:ss";
  }

Preserving for compatibility
+ (NSString *) dbformatstring {
return [NSDate timestampformatstring];
}
@end

"Date operation for iOS class extensions" Nsdate+helpers