我想要两个NSInteger年,月再去一个月。例如现在是2011-01我怎样才能得到2010-12。增加是一回事,但我想减少。希望有人能帮助我一点。NSDate减去一个月
NSDate *date = [NSDate date];
NSDateComponents *dateComponents = [calendar components:unitFlags fromDate:date];
NSInteger year = [dateComponents year];
NSInteger month = [dateComponents month];
[calendar release];
NSString * pdf_name = [NSString stringWithFormat:@"file_%d_%02d.pdf", year, month];
招呼内
编辑:我的解决方案
NSCalendar *calendar= [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSCalendarUnit unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit;
NSDate *date = [NSDate date];
NSDateComponents *dateComponents = [calendar components:unitFlags fromDate:date];
NSInteger year = [dateComponents year];
NSInteger month = [dateComponents month];
BOOL substractOneMonth = YES;
if (substractOneMonth) {
if (month==1) {
year--;
month = 12;
}else {
month--;
}
}
[calendar release];
NSString * pdf_name = [NSString stringWithFormat:@"file_%d_%02d.pdf", year, month];
对不起,当我即将与您的解决方案即时获得:4021-12-12 08:32:40 +0000 – 2011-01-06 03:47:56