delete . while seraching in serach bar for iphone

Question

after getting result from my search in search bar i am putting a "." in that search bar text field as i need that

but i want to omit that in this function so that next time i get a empty serachbar for fresh serach

- (void) searchBarTextDidBeginEditing:(UISearchBar *)theSearchBar {
    //searchBar.text = @"\n";
}

how can i delete that . from searchBar