iOS--对iOS时间类的代码总结 NSCalendar NSDateComponents NSDate

前一段时间感觉苹果的时间类很乱，但是经过仔细琢磨，感觉苹果对时间类的架构还是非常好的，下面是我读苹果官方文档，并总结下来的代码，如果有什么错的地方还请指出。
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////.h

//
// DateHelper.m
// TestDate
//代码原始地址：http://blog.csdn.net/diyagoanyhacker
// Created by 禚来强 email：ZhuoLaiQiang@Gmail.com QQ：1287976580
// Copyright (c) 2012年 __MyCompanyName__. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface DateHelper : NSObject

/************************************************
*获取日期（date_）对用的元素
*/
+ (int)second:(NSDate *)date_;
+ (int)minute:(NSDate *)date_;
+ (int)hour:(NSDate *)date_;
+ (int)day:(NSDate *)date_;
+ (int)month:(NSDate *)date_;
+ (int)year:(NSDate *)date_;
/************************************************/

/************************************************
*判断date_是否和当前日期在指定的范围之内
*/
+ (BOOL)isDateThisWeek:(NSDate *)date_;
+ (BOOL)isDateThisMonth:(NSDate *)date_;
+ (BOOL)isDateThisYear:(NSDate *)date_;
/************************************************/

/************************************************
*判断两个时间是否在指定的范围之内
*/
+ (BOOL)twoDateIsSameYear:(NSDate *)fistDate_
second:(NSDate *)secondDate_;
+ (BOOL)twoDateIsSameMonth:(NSDate *)fistDate_
second:(NSDate *)secondDate_;
+ (BOOL)twoDateIsSameDay:(NSDate *)fistDate_
second:(NSDate *)secondDate_;
/************************************************/

/* 获取指定日期所在月的天数 */
+ (int)numberDaysInMonthOfDate:(NSDate *)date_;

+ (NSDate *)dateByAddingComponents:(NSDate *)date_
offsetComponents:(NSDateComponents *)offsetComponents_;

/************************************************
*获取指定日期所在的月对应的月开始时间和月结束时间
*/
+ (NSDate *)startDateInMonthOfDate:(NSDate *)date_;
+ (NSDate *)endDateInMonthOfDate:(NSDate *)date_;
/************************************************/

- (BOOL)isDateThisWeek:(NSDate *)date;

@end

.m
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////.m

//
// DateHelper.m
// TestDate
//代码原始地址：http://blog.csdn.net/diyagoanyhacker
// Created by 禚来强 email：ZhuoLaiQiang@Gmail.com QQ：1287976580 电话：18671682672 on 12-3-7.
// Copyright (c) 2012年 __MyCompanyName__. All rights reserved.
//

#import "DateHelper.h"

@interface DateHelper()

+ (int)ordinality:(NSDate *)date_ ordinalitySign:(NSCalendarUnit)ordinalitySign_;

@end

@implementation DateHelper

#pragma mark - 外部接口

+ (int)second:(NSDate *)date_
{
int ordinality = [DateHelperordinality: date_ordinalitySign:NSSecondCalendarUnit];

return ordinality;
}

+ (int)minute:(NSDate *)date_
{
int ordinality = [DateHelperordinality: date_ordinalitySign:NSMinuteCalendarUnit];

return ordinality;
}

+ (int)hour:(NSDate *)date_
{
int ordinality = [DateHelperordinality: date_ordinalitySign:NSHourCalendarUnit];

return ordinality;
}

+ (int)day:(NSDate *)date_
{
int ordinality = [DateHelperordinality: date_ordinalitySign:NSDayCalendarUnit];

return ordinality;
}

+ (int)month:(NSDate *)date_
{
int ordinality = [DateHelperordinality: date_ordinalitySign:NSMonthCalendarUnit];

return ordinality;
}

+ (int)year:(NSDate *)date_
{
int ordinality = [DateHelperordinality: date_ordinalitySign:NSYearCalendarUnit];

return ordinality;
}

/* 判断date_是否在当前星期 */
+ (BOOL)isDateThisWeek:(NSDate *)date_
{
NSDate *start;
NSTimeInterval extends;
NSCalendar *cal=[NSCalendarautoupdatingCurrentCalendar];
NSDate *today=[NSDatedate];
BOOL success= [calrangeOfUnit:NSWeekCalendarUnitstartDate:&start
interval: &extendsforDate:today];
if(!success)returnNO;
NSTimeInterval dateInSecs = [date_timeIntervalSinceReferenceDate];
NSTimeInterval dayStartInSecs= [start
timeIntervalSinceReferenceDate];
if(dateInSecs > dayStartInSecs && dateInSecs < (dayStartInSecs+extends))
{
return YES;
}
else
{
return NO;
}
}

+ (BOOL)isDateThisMonth:(NSDate *)date_
{
NSDate *start;
NSTimeInterval extends;
NSCalendar *cal=[NSCalendarautoupdatingCurrentCalendar];
NSDate *today=[NSDatedate];
BOOL success= [calrangeOfUnit:NSMonthCalendarUnit
startDate: &start
interval: &extendsforDate:today];
if(!success) returnNO;
NSTimeInterval dateInSecs = [date_timeIntervalSinceReferenceDate];
NSTimeInterval dayStartInSecs= [start
timeIntervalSinceReferenceDate];
if(dateInSecs > dayStartInSecs && dateInSecs < (dayStartInSecs+extends))
{
return YES;
}
else
{
return NO;
}
}

+ (BOOL)isDateThisYear:(NSDate *)date_
{
NSDate *start;
NSTimeInterval extends;
NSCalendar *cal=[NSCalendarautoupdatingCurrentCalendar];
NSDate *today=[NSDatedate];
BOOL success= [calrangeOfUnit:NSYearCalendarUnit
startDate: &start
interval: &extendsforDate:today];
if(!success)returnNO;
NSTimeInterval dateInSecs = [date_timeIntervalSinceReferenceDate];
NSTimeInterval dayStartInSecs= [start
timeIntervalSinceReferenceDate];
if(dateInSecs > dayStartInSecs && dateInSecs < (dayStartInSecs+extends))
{
return YES;
}
else
{
return NO;
}
}

+ (BOOL)twoDateIsSameYear:(NSDate *)fistDate_
second:(NSDate *)secondDate_
{
NSCalendar *calendar = [NSCalendarcurrentCalendar];
int unit =NSYearCalendarUnit;

NSDateComponents *fistComponets = [calendarcomponents: unitfromDate: fistDate_];
NSDateComponents *secondComponets = [calendarcomponents: unit

fromDate: secondDate_];

if ([fistComponets year] == [secondComponetsyear])
{
return YES;
}

return NO;
}

+ (BOOL)twoDateIsSameMonth:(NSDate *)fistDate_
second:(NSDate *)secondDate_
{
NSCalendar *calendar = [NSCalendarcurrentCalendar];
int unit =NSMonthCalendarUnit |NSYearCalendarUnit;

NSDateComponents *fistComponets = [calendarcomponents: unitfromDate: fistDate_];
NSDateComponents *secondComponets = [calendarcomponents: unit

fromDate: secondDate_];

if ([fistComponets month] == [secondComponetsmonth]
&& [fistComponets year] == [secondComponetsyear])
{
return YES;
}

return NO;
}

+ (BOOL)twoDateIsSameDay:(NSDate *)fistDate_
second:(NSDate *)secondDate_
{
NSCalendar *calendar = [NSCalendarcurrentCalendar];
int unit =NSMonthCalendarUnit |NSYearCalendarUnit |NSDayCalendarUnit;

NSDateComponents *fistComponets = [calendarcomponents: unit

fromDate: fistDate_];
NSDateComponents *secondComponets = [calendarcomponents: unit

fromDate: secondDate_];

if ([fistComponets day] == [secondComponetsday]
&& [fistComponets month] == [secondComponetsmonth]
&& [fistComponets year] == [secondComponetsyear])
{
return YES;
}

return NO;
}

+ (int)numberDaysInMonthOfDate:(NSDate *)date_
{
NSCalendar *calender = [NSCalendarcurrentCalendar];
NSRange range = [calenderrangeOfUnit:NSDayCalendarUnit
inUnit:
NSMonthCalendarUnit
forDate: date_];

return range.length;
}

+ (NSDate *)dateByAddingComponents:(NSDate *)date_
offsetComponents:(NSDateComponents *)offsetComponents_
{
NSCalendar *gregorian = [[[NSCalendaralloc]initWithCalendarIdentifier:NSGregorianCalendar]autorelease];
NSDate *endOfWorldWar3 = [gregorian
dateByAddingComponents: offsetComponents_

toDate: date_

options: 0];

return endOfWorldWar3;
}

+ (NSDate *)startDateInMonthOfDate:(NSDate *)date_
{
double interval = 0;
NSDate *beginningOfMonth =
nil;
NSCalendar *gregorian = [NSCalendarcurrentCalendar];
BOOL ok = [gregorianrangeOfUnit:NSMonthCalendarUnit
startDate: &beginningOfMonth
interval: &interval
forDate: date_];

if (ok)
{
return beginningOfMonth;
}
else
{
return nil;
}
}

+ (NSDate *)endDateInMonthOfDate:(NSDate *)date_
{
double interval = 0;
NSDate *beginningOfMonth =
nil;
NSCalendar *gregorian = [NSCalendarcurrentCalendar];
BOOL ok = [gregorianrangeOfUnit:NSMonthCalendarUnit
startDate: &beginningOfMonth
interval: &interval
forDate: date_];

if (ok)
{
NSDate *endDate = [beginningOfMonthaddTimeInterval: interval];

return endDate;
}
else
{
return nil;
}
}

- (BOOL)isDateThisWeek:(NSDate *)date
{
NSDate *start;
NSTimeInterval extends;
NSCalendar *cal=[NSCalendarautoupdatingCurrentCalendar];
NSDate *today=[NSDatedate];
BOOL success= [calrangeOfUnit:NSWeekCalendarUnitstartDate:&start
interval: &extendsforDate:today];
if(!success)returnNO;
NSTimeInterval dateInSecs = [datetimeIntervalSinceReferenceDate];
NSTimeInterval dayStartInSecs= [start
timeIntervalSinceReferenceDate];
if(dateInSecs > dayStartInSecs && dateInSecs < (dayStartInSecs+extends)){
return YES;
}
else {
return NO;
}
}

#pragma mark - 私有方法

+ (int)ordinality:(NSDate *)date_ ordinalitySign:(NSCalendarUnit)ordinalitySign_
{
int ordinality = -1;

if (ordinalitySign_ <
NSEraCalendarUnit || ordinalitySign_ > NSWeekdayOrdinalCalendarUnit)
{
return ordinality;
}

NSCalendar *calendar = [NSCalendarcurrentCalendar];
NSDateComponents *components = [calendarcomponents: ordinalitySign_fromDate: date_];
switch (ordinalitySign_)
{
caseNSSecondCalendarUnit:
{
ordinality = [components second];
break;
}
caseNSMinuteCalendarUnit:
{
ordinality = [components minute];
break;
}
caseNSHourCalendarUnit:
{
ordinality = [components hour];
break;
}
caseNSDayCalendarUnit:
{
ordinality = [components day];
break;
}
caseNSMonthCalendarUnit:
{
ordinality = [components month];
break;
}
caseNSYearCalendarUnit:
{
ordinality = [components year];
break;
}

default:
break;
}

return ordinality;
}

@end