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PHP

PageNavigator.object：源码内容

							<?php
class PageNavigator {
   var $first_page;
   var $last_page;
   var $first_item;
   var $last_item;
   var $num_items;
   var $num_items_per_page;
   var $current_page;
   var $next_page;
   var $previous_page;
   Function PageNavigator() {
      $this->first_page = 0;
      $this->last_page  = 0;
      $this->first_item = 0;
      $this->last_item  = 0;
      $this->num_items  = 0;
      $this->num_items_per_page = 0;
      $this->current_page  = 0;
   }
   Function Calculate() {
      if ( $this->num_items == 0 ) {
         return;
      }
      if ( $this->num_items_per_page == 0 ) {
         return;
      }
      $this->first_page = 1;
      $this->last_page = 
         ceil( $this->num_items / $this->num_items_per_page );
      if ( $this->current_page == 0 ) {
         return;
      }
      $this->previous_page = $this->current_page - 1 ;
      if ( $this->previous_page <= 0 ) {
         $this->previous_page = 1;
      }
      $this->next_page     = $this->current_page + 1;
      if ( $this->next_page > $this->last_page ) {
         $this->next_page = $this->last_page;
      }
      $this->last_item  = 0;
      $this->last_item  = $this->num_items_per_page * $this->current_page;
      if ( $this->last_item > $this->num_items ) {
         $this->last_item = $this->num_items;
      }
      $this->first_item = 0;
      $this->first_item = 
         ($this->num_items_per_page * ($this->current_page - 1 ));
      if ( $this->first_item < 0 ) {
         $this->first_item = 0;
      }
      if ( $this->first_item == 0 ) {
         $this->first_item = 1;
      }
   }
}
?>

						