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