IOS Object-c NSDate总结日期操作
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1?//?当前时间创建NSDate
? ? ? ??NSDate?*myDate = [NSDate?date];
? ? ? ??NSLog(@"myDate = %@",myDate);
2?//从现在开始的24小时
? ? ? ??NSTimeInterval?secondsPerDay =?24*60*60;
? ? ? ??NSDate?*tomorrow = [NSDate?dateWithTimeIntervalSinceNow:secondsPerDay];
? ? ? ??NSLog(@"myDate = %@",tomorrow);
3//根据已有日期创建日期
?? ? ? ??NSTimeInterval?secondsPerDay1 =?24*60*60;
? ? ? ??NSDate?*now = [NSDate?date];
? ? ? ??NSDate?*yesterDay = [now?addTimeInterval:-secondsPerDay1];
? ? ? ??NSLog(@"yesterDay = %@",yesterDay);
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?4//比较日期
? ? ? ??BOOL?sameDate = [now?isEqualToDate:yesterDay];
? ? ? ??NSLog(@"sameDate = %lu",sameDate);
? ? ? ??4.1//获取较早的日期
? ? ? ??NSDate?*earlierDate = [yesterDay?earlierDate:now];
? ? ? ??NSLog(@"earlierDate? = %@",earlierDate);
? ? ? ??4.2//较晚的日期
? ? ? ??NSDate?*laterDate = [yesterDay?laterDate:now];
? ? ? ??NSLog(@"laterDate? = %@",laterDate);
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? ? ? ??//两个日期之间相隔多少秒
? ? ? ??NSTimeInterval?secondsBetweenDates= [yesterDay?timeIntervalSinceDate:now];
? ? ? ??NSLog(@"secondsBetweenDates=? %lf",secondsBetweenDates);
? ? ? ??//通过NSCALENDAR类来创建日期
? ? ? ??NSDateComponents?*comp = [[NSDateComponentsalloc]init];
? ? ? ? [comp?setMonth:06];
? ? ? ? [comp?setDay:01];
? ? ? ? [comp?setYear:2001];
? ? ? ??NSCalendar?*myCal = [[NSCalendaralloc]initWithCalendarIdentifier:NSGregorianCalendar];
? ? ? ??NSDate?*myDate1 = [myCal?dateFromComponents:comp];
? ? ? ??NSLog(@"myDate1 = %@",myDate1);
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? ? ? ??//从已有日期获取日期
? ? ? ??unsigned?units? =?NSMonthCalendarUnit|NSDayCalendarUnit|NSYearCalendarUnit;
? ? ? ??NSDateComponents?*comp1 = [myCal?components:units?fromDate:now];
? ? ? ??NSInteger?month = [comp1?month];
? ? ? ??NSInteger?year = [comp1?year];
? ? ? ??NSInteger?day = [comp1?day];
? ? ? ??//NSDateFormatter实现日期的输出
? ? ? ??NSDateFormatter?*formatter = [[NSDateFormatteralloc]init];
? ? ? ? [formatter?setDateStyle:NSDateFormatterFullStyle];//直接输出的话是机器码
? ? ? ??//或者是手动设置样式[formatter setDateFormat:@"yyyy-mm-dd"];
? ? ? ??NSString?*string = [formatter?stringFromDate:now];
? ? ? ??NSLog(@"string = %@",string);
? ? ? ??NSLog(@"formater = %@",formatter);
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//获取日期格式对象
- (NSDateFormatter *)dateFormatter {
if (dateFormatter == nil) {
dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateStyle:NSDateFormatterMediumStyle];
[dateFormatter setTimeStyle:NSDateFormatterNoStyle];
}
return dateFormatter;
}
