How to go from last row to first row direstly in uitableview?

iam making one application.In that iam using UITableview.In that i places one button at the last row of the tableview.How we go to firs开发者_开发问答t row when we click on that button.So please tell me how to solve this one.

Use this:

NSIndexPath *topIndexPath;
topIndexPath = [NSIndexPath indexPathForRow:0 inSection:0];
[tableView scrollToRowAtIndexPath:topIndexPath atScrollPosition:UITableViewScrollPositionTop animated:NO];