学步园

在 NSDate中获得时间信息，年、月、星期、日、时、分、秒和毫秒：

注：第一种方法不能获取毫秒的信息，最后利用第二种方法实现了获取毫秒的信息

NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar]; 
NSDate *now; 
NSDateComponents *comps = [[NSDateComponents alloc] init]; 
NSInteger unitFlags = NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit | NSWeekdayCalendarUnit | 
NSHourCalendarUnit | NSMinuteCalendarUnit | NSSecondCalendarUnit; 
now=[NSDate date]; 
comps = [calendar components:unitFlags fromDate:now]; 
int year=[comps year]; 
int week = [comps weekday];    
int month = [comps month]; 
int day = [comps day]; 
int hour = [comps hour]; 
int min = [comps minute]; 
int sec = [comps second]; 

NSDataToNSString方法： 

-(NSString *)NSDateToNSTring:(NSDate *)nsDate{ 
  //NSString *string = [nsDate descriptionWithCalendarFormat:@"%Y/%m/%d %H:%M:%S" timeZone:nil locale:nil];此方法为是有API如果要上传APP不要使用 
  NSDateFormatter *fmt = [[[NSDateFormatter alloc] init] autorelease]; 

//  [fmt setDateFormat:@"hh:mm:ss:SSS"]; 

  [fmt setDateFormat:@"yyyy/MM/dd hh:mm:ss:SSS"]; 
  NSString *string=[fmt stringFromDate:nsDate]; 
  return string; 
}

本文转载自：http://hobo86.iteye.com/blog/1013030