如何在目标c ios中以整数形式获取当前年份的当前日期

Question

你好亲爱的我想检索一年中的天数，例如今天是 4 月 10 日，我知道它是每月的第 10 天，但如果我想像今天这样的一年中的一天是一年中的第 99 天怎么办。

这是我到目前为止所做的：

NSInteger todaydaysyear;
NSDateFormatter *yearlyDay = [[NSDateFormatter alloc] init];
[yearlyDay setDateFormat:@"dd-yyyy"];
NSDate *currentdateyear = [NSDate date];
NSString *cureentdatestryear = [yearlyDay stringFromDate:currentdateyear];
NSDate *startDateyear = [yearlyDay dateFromString:cureentdatestryear];
NSDateComponents *componentsyear = [[NSCalendar currentCalendar] components:NSCalendarUnitDay | NSCalendarUnitYear fromDate:startDateyear];
todaydaysyear = [componentsyear day];
NSLog(@"here is the day of the year e.g 99th day but not prints month day why%ld", (long)todaydaysyear);

打印：每月当天的10

张

我想要的：一年中的第99天，耳朵计数的这一天。

答：你如何计算Objective-C中特定日期的一天？

Answer 1

根据 Unicode 技术标准 #35，一年中的日期用 D(1..3 位数字(表示。请记住使用 3 位数字，因为年份可以有 365 天

[yearlyDay setDateFormat:@"DDD-yyyy"];

输出：

@"100-2018">

如果要将其存储为整数，请尝试

NSDate *currentDate = [NSDate date];
NSDateFormatter *formatter = [NSDateFormatter new];
[formatter setDateFormat:@"DDD"];
NSString *string = [formatter stringFromDate:currentDate];
NSInteger dayOfYear = [string integerValue];

Answer 2

使用这个。

//Assuming your calendar is initiated like this
NSCalendar *_calendar = [NSCalendar currentCalendar];
NSInteger yearlyDay;
//Fetch the weekOfYear number
NSInteger weekOfYear = [_calendar component:NSCalendarUnitWeekOfYear fromDate:[NSDate date]];
weekOfYear--;
//Fetch the weekDay number
NSInteger weekDay = [_calendar component:NSCalendarUnitWeekday fromDate:[NSDate date]];
yearlyDay = weekOfYear*7 + weekDay;
NSLog(@"%d", yearlyDay);

或者这个。

NSCalendar *gregorian =
    [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierGregorian];
    NSUInteger dayOfYear =
    [gregorian ordinalityOfUnit:NSCalendarUnitDay
                         inUnit:NSCalendarUnitYear forDate:[NSDate date]];
    NSLog(@"%d", dayOfYear);