iPhone开发--NSDate操作

NSDate //得到当前的日期 NSDate *date = [NSDate date]; NSLog(@"date:%@",date); //得到(24 * 60 * 60)即24小时之前的日期，dateWithTimeIntervalSinceNow: NSDate *yesterday = [NSDate dateWithTimeIntervalSinceNow: -(24 * 60 * 60)]; NSLog(@"yesterday:%@",yesterday); NSDateFormatter *formatter =[[[NSDateFormatter alloc] init] autorelease]; NSDate *date = [NSDate date]; [formatter setTimeStyle:NSDateFormatterMediumStyle]; NSCalendar *calendar = [[[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar] autorelease]; NSDateComponents *comps = [[[NSDateComponents alloc] init] autorelease]; NSInteger unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSWeekdayCalendarUnit | NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit; //int week=0; comps = [calendar components:unitFlags fromDate:date]; int week = [comps weekday]; int year=[comps year]; int month = [comps month]; int day = [comps day]; //[formatter setDateStyle:NSDateFormatterMediumStyle]; //This sets the label with the updated time. int hour = [comps hour]; int min = [comps minute]; int sec = [comps second]; NSLog(@"week%d",week); NSLog(@"year%d",year); NSLog(@"month%d",month); NSLog(@"day%d",day); NSLog(@"hour%d",hour); NSLog(@"min%d",min); NSLog(@"sec%d",sec); //得到毫秒 NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init]; [dateFormatter setDateStyle:NSDateFormatterMediumStyle]; [dateFormatter setTimeStyle:NSDateFormatterShortStyle]; //[dateFormatter setDateFormat:@"hh:mm:ss"] [dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss.SSS"]; NSLog(@"Date%@", [dateFormatter stringFromDate:[NSDate date]]); [dateFormatter release]; ========================================== 方法一 NSDate* toDate1 = [ [ NSDate alloc] initWithString:@"2520-9-26 17:10:00 +0600" ]; NSTimeInterval distance = [ toDate1 timeIntervalSinceNow ]; NSTimeInterval iDat = distance / ( 86400 ) ; NSLog( @" From now to %@ diff: %f ", [toDate1 description ], iDat ); [ toDate1 release ]; 方法二 NSDate* toDate = [ [ NSDate alloc] initWithString:@"2009-9-29 0:0:00 +0600" ]; NSDate* startDate = [ [ NSDate alloc] init ]; NSCalendar* chineseClendar = [ [ NSCalendar alloc ] initWithCalendarIdentifier:NSGregorianCalendar ]; NSUInteger unitFlags = NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit | NSDayCalendarUnit | NSMonthCalendarUnit | NSYearCalendarUnit; NSDateComponents *cps = [ chineseClendar components:unitFlags fromDate:startDate toDate:toDate options:0]; NSInteger diffHour = [ cps hour ]; NSInteger diffMin = [ cps minute ]; NSInteger diffSec = [ cps second ]; NSInteger diffDay = [ cps day ]; NSInteger diffMon = [ cps month ]; NSInteger diffYear = [ cps year ]; NSLog( @" From Now to %@, diff: Years: %d Months: %d, Days; %d, Hours: %d, Mins:%d, sec:%d", [toDate description], diffYear, diffMon, diffDay, diffHour, diffMin,diffSec ); [ toDate release ]; [ startDate release ]; [ chineseClendar release ];