ios-学习点－日历工具类

#import <Foundation/Foundation.h>
#import "monthModel.h"
#import "dayModel.h"
#import "SolarAndLunerHeader.h"

@interface PublicUtils : NSObject
#pragma mark将时间本地化
+(NSDate *)getLocalDataWithData:(NSDate *)date;

#pragma mark获取天数
+(NSRange)getRangefromSmallUtilInBigUtil:(NSDate *)date;

#pragma mark获取小单位在大单位中得系数，主要用于根据日期获得今天是星期几，默认setfirstweekday为1就是从周日开头的
+(NSInteger)getCountFromSmallUtilInBigUtil:(NSDate *)date;

#pragma mark 获得当前月第一天的日期
+(NSDate *)getCurrentMonthFirstDay;

#pragma mark 获得次月第一天的日期
+(NSDate *)getnextMonthFirstDay;

#pragma mark 组装一个空白数据，当月到次月的数据没有变化的封装，具体细节由服务器中取出的数据再维护一下得出真实的数据
+(NSMutableArray *)createFixedDData;


#pragma mark 同步月份数据，只是星期同步
+(void)copyWeekWithDictionary:(NSMutableArray *)array;

@end

/*
 1.date 转 NSDateComponents 通过日历会将时间本地化
 2.反过来，NSDateComponents 转date 会逆向行为会讲转出来的时间会转到0时区的时间
 总结：本地时间转NSDateComponents用本地化日历转的话，最好将日历的时区设置为0时区，否则就会2次本地化时间出错
 反过来也一样。
 */

#import "PublicUtils.h"

@implementation PublicUtils
#pragma mark将时间本地化
+(NSDate *)getLocalDataWithData:(NSDate *)date{
   NSTimeZone *timezone= [NSTimeZone systemTimeZone];
   NSInteger interval= [timezone secondsFromGMT];
  return  [date dateByAddingTimeInterval:interval];
}


#pragma mark获取天数
+(NSRange)getRangefromSmallUtilInBigUtil:(NSDate *)date{
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSRange range = [calendar rangeOfUnit:NSCalendarUnitDay inUnit:NSCalendarUnitMonth forDate:date];
    return range;
}

#pragma mark获取小单位在大单位中得系数，主要用于根据日期获得今天是星期几，默认setfirstweekday为1就是从周日开头的
+(NSInteger)getCountFromSmallUtilInBigUtil:(NSDate *)date{
   NSCalendar *calendar = [NSCalendar currentCalendar];
  return  [calendar ordinalityOfUnit:NSCalendarUnitWeekday inUnit:NSCalendarUnitWeekOfMonth forDate:date];
}


#pragma mark 获得当前月第一天的日期
+(NSDate *)getCurrentMonthFirstDay{
   NSDate *date= [NSDate date];
   NSCalendar *calender= [NSCalendar currentCalendar];
   NSDateComponents *compt= [calender components:(NSCalendarUnitYear|NSCalendarUnitMonth|NSCalendarUnitDay) fromDate:date];
  [compt setDay:1];
   NSDate *currentdate= [calender dateFromComponents:compt];
  return [PublicUtils getLocalDataWithData:currentdate];
}

#pragma mark 获得次月第一天的日期
+(NSDate *)getnextMonthFirstDay{
    NSDate *date= [NSDate date];
    NSCalendar *calender= [NSCalendar currentCalendar];//同比下面这个不用转成0时区
    NSDateComponents *compt= [calender components:(NSCalendarUnitYear|NSCalendarUnitMonth|NSCalendarUnitDay) fromDate:date];
    if (compt.month==12) {
        [compt setMonth:compt.month+1];
        [compt setYear:compt.year+1];
    }else {
        [compt setMonth:compt.month+1];
    }
     [compt setDay:1];
    NSDate *currentdate= [calender dateFromComponents:compt];
    return [PublicUtils getLocalDataWithData:currentdate];

}

#pragma mark 从日期里面获取各个元素
+(NSDateComponents *)changeToCompontsFromDate:(NSDate *)date{
    NSCalendar *calender= [NSCalendar currentCalendar];
    [calender setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];//(设置这个的目的，传进来的是一个本地时间，再用本地是日历转一次，就会造成2次本地化就会有误差，所以将日历的时区转成0时区，来避免2次转换)
    NSDateComponents *compt= [calender components:(NSCalendarUnitYear|NSCalendarUnitMonth|NSCalendarUnitDay|NSCalendarUnitHour|NSCalendarUnitMinute|NSCalendarUnitSecond) fromDate:date];
    return compt;
}