NSDate倒数天数

| 我想创建一个日期之前的天数倒计时。我对小时或分钟不感兴趣，而对从当前日期到设置日期的天数不感兴趣。这就是我一直在尝试的：

    NSDate *date = [NSDate date];
NSString *dateString = [date description];
// this **dateString** string will have **\"yyyy-MM-dd HH:mm:ss +0530\"**
//  NSMutableString *mutString = dateString;
NSArray *arr = [dateString componentSeperatedByString:@\" \"];
// arr will have [0] -> yyyy-MM-dd, [1] -> HH:mm:ss, [2] -> +0530 (time zone)

但这不起作用，因为当前日期以分钟和秒为单位给出时间。

//NSDate *currentDate = [[NSDate alloc] init];
NSString *start = [arr objectAtIndex:0];//[NSString stringWithFormat:@\"%@\", currentDate];//@\"2011-11-05\";
NSLog(@\"%@\",start);
NSString *end = @\"2011-6-03\";

NSDateFormatter *f = [[NSDateFormatter alloc] init];
[f setDateFormat:@\"yyyy-MM-dd\"];
NSDate *startDate = [f dateFromString:start];
NSDate *endDate = [f dateFromString:end];
[f release];

NSCalendar *gregorianCalendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *components = [gregorianCalendar components:NSDayCalendarUnit
                                                    fromDate:startDate
                                                      toDate:endDate
                                                     options:0];
NSInteger days = [components day];
[gregorianCalendar release];
NSLog(@\"%i\", days);

我不太了解这段代码，我不熟悉NSDate和格式化程序，但这是我的一堆Internet代码的组合。提前致谢。

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3 个回复

耐钨徒

您可以通过这种方式计算从当天开始的天数。 NSDate NewDate =这是您的比较日期； NSDateComponents * dateComp = [[NSDateComponents alloc] init];

NSCalendar *Calander = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];

NSDateFormatter *dateFormat=[[NSDateFormatter alloc] init];

NSDateComponents *comps=[[NSDateComponents alloc] init];

unsigned int unitFlags = NSDayCalendarUnit | NSMonthCalendarUnit | NSYearCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;

dateComp = [Calander components:unitFlags fromDate:[NSDate date]];

[dateFormat setDateFormat:@\"dd\"];
[comps setDay:[[dateFormat stringFromDate:[NSDate date]] intValue]];
[dateFormat setDateFormat:@\"MM\"];
[comps setMonth:[[dateFormat stringFromDate:[NSDate date]] intValue]];
[dateFormat setDateFormat:@\"yyyy\"];
[comps setYear:[[dateFormat stringFromDate:[NSDate date]] intValue]];
[dateFormat setDateFormat:@\"HH\"];
[comps setHour:05];
[dateFormat setDateFormat:@\"mm\"];
[comps setMinute:30];

NSDate *currentDate=[Calander dateFromComponents:comps];

//NSLog(@\"Current Date is :- \'%@\'\",currentDate);

dateComp = [Calander components:unitFlags fromDate:newDate];

    [dateFormat setDateFormat:@\"dd\"];
    [comps setDay:[[dateFormat stringFromDate:newDate] intValue]];
    [dateFormat setDateFormat:@\"MM\"];
    [comps setMonth:[[dateFormat stringFromDate:newDate] intValue]];
    [dateFormat setDateFormat:@\"yyyy\"];
    [comps setYear:[[dateFormat stringFromDate:newDate] intValue]];
    [dateFormat setDateFormat:@\"HH\"];
    [comps setHour:05];
    [dateFormat setDateFormat:@\"mm\"];
    [comps setMinute:30];

    NSDate *reminderDate=[Calander dateFromComponents:comps];

    //NSLog(@\"Current Date is :- \'%@\'\",reminderDate);

    //NSLog(@\"Current Date is :- \'%@\'\",currentDate);

    NSTimeInterval ti = [reminderDate timeIntervalSinceDate:currentDate];

    //NSLog(@\"Time Interval is :- \'%f\'\",ti);
    int days = ti/86400;

鲁釜头

您可以使用ѭ3来缩短时间：

NSDate* targetDate = ...
NSDate* today = [NSDate date]

NSCalendar* cal = [NSCalendar currentCalendar]

unsigned unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit |  NSDayCalendarUnit;
targetDate = [cal dateFromComponents:[cal components:unitFlags fromDate:targetDate]];
today = [cal dateFromComponents:[cal components:unitFlags fromDate:today]];

然后通过仅指定day日期单位来获取天数的差异（如果没有上面的代码，这可能会起作用，我不确定）：

int days = [[cal components:NSDayCalendarUnit fromDate:today  toDate:targetDate  options:0] day];

垫歌蝎降凤

使用以下代码，

NSTimeInterval dateDiff = [eventDate timeIntervalSinceNow];
int countDown=trunc(dateDiff/(60*60*24));

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NSDate倒数天数

3 个回复

发起人

iphone

nsdate

objective_c

问题状态

NSDate倒数天数

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3 个回复

发起人

iphone

nsdate

objective_c

问题状态