一ヶ月前の今日を取得するには NSCalendar *calendar = [[NSCalendar currentCalendar]; NSDateComponents *comps = [[[NSDateComponents alloc] init] autorelease]; comps.month = -1; NSDate *date = [calendar dateByAddingComponents:comps toDate:[NSDate date]]; 今月の1日を取得するには NSCalendar *calendar = [[NSCalendar currentCalendar]; unsigned unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit; NSDateComponents *comps = [calend
![NSCalendar & NSDateComponents - めもめも](https://cdn-ak-scissors.b.st-hatena.com/image/square/b41eef31275b52d41e7745943dec1b58441b8e0d/height=288;version=1;width=512/http%3A%2F%2Fsisyamo.cocolog-nifty.com%2F.shared-pleasy%2Fnifty_managed%2Fimages%2Fweb%2Fogp%2Fdefault.png)