How to simulate keypress event for "page down" keyboard button ?

["Govinda Parida" <govinda parida gmail com>]

Hi, I have added a Gtk::TreeView control in a Gtk::Window and at the right side of the treeview, I have added a Gtk::Button. when this button is clicked the keypress event to the "page down" key should be generated to view the next page of treeview. How do I generate keypress event for "page down" key. please give me some clues.