在Objective-C中获取NSDate中每月的天数？

Question

所以我一直试图在一个int中找到这个月的最后一天，但我使用的代码总是认为最后一天是30

我使用的代码看起来像这样

NSDate *curDate = [NSDate date];
    NSCalendar* calendar = [NSCalendar currentCalendar];
    NSDateComponents* compsd = [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSWeekCalendarUnit|NSWeekdayCalendarUnit fromDate:curDate]; // Get necessary date components

    // set last of month
    [compsd setMonth:[compsd month]+1];
    [compsd setDay:0];
    NSDate *tDateMonth = [calendar dateFromComponents:compsd];
    //NSLog(@"%@", tDateMonth);

    //[comps setMonth:[comps month]+1];
    //[comps setDay:0];
   // NSDate *tDateMonth = [cal dateFromComponents:comps];
    //NSLog(@"%@", tDateMonth);
     //*/

    NSString *tDateString = [NSString stringWithFormat:@"%@", tDateMonth];
    NSString *dateNTime = [[tDateString componentsSeparatedByString:@"-"] objectAtIndex:2];
    int justDate = [[[dateNTime componentsSeparatedByString:@" "] objectAtIndex:0] intValue];
    NSLog(@"Last Day of %@ is %d", monthName, justDate);

我错过了什么？

Answer 1

试试这个简单的方法：

NSCalendar *cal = [NSCalendar currentCalendar];
NSRange rng = [cal rangeOfUnit:NSDayCalendarUnit 
                        inUnit:NSMonthCalendarUnit
                       forDate:[NSDate date]];
NSUInteger numberOfDaysInMonth = rng.length;

Answer 2

我想你可以尝试这样的事情

NSDate *currentDate = [NSDate date];
NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *components = [calendar components:NSYearCalendarUnit|NSMonthCalendarUnit|NSWeekCalendarUnit|NSWeekdayCalendarUnit fromDate:currentDate];

[components setMonth:[components month]+1];
[components setDay:0];
NSDate *theDate = [calendar dateFromComponents:components];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"d"];
[dateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];

NSString *dateString = [dateFormatter stringFromDate:theDate];
NSInteger dateInt = [dateString intValue];
NSLog(@"The int: %i", dateInt);