IOS--方法积累

1.

计算两个日期之间相差几天几小时几分钟

　　NSDateFormatter *dateFormatter=[[NSDateFormatter alloc] init];

   [dateFormatter setDateFormat:@"yyyy-MM-dd HH:mm:ss"];

   NSDate *  senddate=[NSDate date];

   //结束时间

   NSDate *endDate = [dateFormatter dateFromString:@"2014-6-24 00:00:00"];

   //当前时间

   NSDate *senderDate = [dateFormatter dateFromString:[dateFormatter stringFromDate:senddate]];

   //得到相差秒数

   NSTimeInterval time=[endDate timeIntervalSinceDate:senderDate];

    

   int days = ((int)time)/(3600*24);

   int hours = ((int)time)%(3600*24)/3600;

   int minute = ((int)time)%(3600*24)600/60;

   

   if (days <= 0&&hours; <= 0&&minute; <= 0)

       dateContent=@"0天0小时0分钟";

   else

       dateContent=[[NSString alloc] initWithFormat:@"%i天%i小时%i分钟",days,hours,minute];

 

2.动画执行完之后才执行某动作：

                [CATransaction begin];

                [CATransaction setCompletionBlock:^{

                    // animation has finished

                }];

　　　　　　 // do some work eg：

                [_myTableView beginUpdates];

                [_insurancePeopleArray removeObjectAtIndex:deleteIndex-10-1];

                NSIndexPath * indexPathOld = [NSIndexPath indexPathForRow:deleteIndex-10 inSection:0];

                NSArray *array=[NSArray arrayWithObjects:indexPathOld, nil];

                [self.myTableView deleteRowsAtIndexPaths:array withRowAnimation:UITableViewRowAnimationFade];

                [_myTableView endUpdates];

                [CATransaction commit];