一个section刷新
NSIndexSet *indexSet=[[NSIndexSet alloc]initWithIndex:2];
[tableview reloadSections:indexSetwithRowAnimation:UITableViewRowAnimationAutomatic];
一个cell刷新
NSIndexPath *indexPath=[NSIndexPath indexPathForRow:3 inSection:0]; [tableView reloadRowsAtIndexPaths:[NSArray arrayWithObjects:indexPath,nil]withRowAnimation:UITableViewRowAnimationNone];
