pagenav.php

讲的是网络编程

<?php
// $Id: pagenav.php 1057 2007-09-17 07:05:32Z dugris $
//  ------------------------------------------------------------------------ //
//                XOOPS - PHP Content Management System                      //
//                    Copyright (c) 2000 XOOPS.org                           //
//                       <http://www.xoops.org/>                             //
//  ------------------------------------------------------------------------ //
//  This program is free software; you can redistribute it and/or modify     //
//  it under the terms of the GNU General Public License as published by     //
//  the Free Software Foundation; either version 2 of the License, or        //
//  (at your option) any later version.                                      //
//                                                                           //
//  You may not change or alter any portion of this comment or credits       //
//  of supporting developers from this source code or any supporting         //
//  source code which is considered copyrighted (c) material of the          //
//  original comment or credit authors.                                      //
//                                                                           //
//  This program is distributed in the hope that it will be useful,          //
//  but WITHOUT ANY WARRANTY; without even the implied warranty of           //
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the            //
//  GNU General Public License for more details.                             //
//                                                                           //
//  You should have received a copy of the GNU General Public License        //
//  along with this program; if not, write to the Free Software              //
//  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA //
//  ------------------------------------------------------------------------ //
// Author: Kazumi Ono (AKA onokazu)                                          //
// URL: http://www.myweb.ne.jp/, http://www.xoops.org/, http://jp.xoops.org/ //
// Project: The XOOPS Project                                                //
// ------------------------------------------------------------------------- //

/**
 * Class to facilitate navigation in a multi page document/list
 *
 * @package		kernel
 * @subpackage	util
 *
 * @author		Kazumi Ono 	<[e-mail]>
 * @copyright	(c) 2000-2003 The Xoops Project - www.xoops.org
 */
class XoopsPageNav
{
	/**#@+
	 * @access	private
	 */
	var $total;
	var $perpage;
	var $current;
	var $url;
    /**#@-*/

	/**
	 * Constructor
	 *
	 * @param   int     $total_items    Total number of items
	 * @param   int     $items_perpage  Number of items per page
	 * @param   int     $current_start  First item on the current page
	 * @param   string  $start_name     Name for "start" or "offset"
	 * @param   string  $extra_arg      Additional arguments to pass in the URL
	 **/
	function XoopsPageNav($total_items, $items_perpage, $current_start, $start_name="start", $extra_arg="")
	{
		$this->total = intval($total_items);
		$this->perpage = intval($items_perpage);
		$this->current = intval($current_start);
		if ( $extra_arg != '' && ( substr($extra_arg, -5) != '&amp;' || substr($extra_arg, -1) != '&' ) ) {
			$extra_arg .= '&amp;';
		}
		$this->url = $_SERVER['PHP_SELF'].'?'.$extra_arg.trim($start_name).'=';
	}

	/**
	 * Create text navigation
	 *
	 * @param   integer $offset
	 * @return  string
	 **/
	function renderNav($offset = 4)
	{
		$ret = '';
		if ( $this->total <= $this->perpage ) {
			return $ret;
		}
		$total_pages = ceil($this->total / $this->perpage);
		if ( $total_pages > 1 ) {
			$prev = $this->current - $this->perpage;
			if ( $prev >= 0 ) {
				$ret .= '<a href="'.$this->url.$prev.'"><u>&laquo;</u></a> ';
			}
			$counter = 1;
			$current_page = intval(floor(($this->current + $this->perpage) / $this->perpage));
			while ( $counter <= $total_pages ) {
				if ( $counter == $current_page ) {
					$ret .= '<b>('.$counter.')</b> ';
				} elseif ( ($counter > $current_page-$offset && $counter < $current_page + $offset ) || $counter == 1 || $counter == $total_pages ) {
					if ( $counter == $total_pages && $current_page < $total_pages - $offset ) {
						$ret .= '... ';
					}
					$ret .= '<a href="'.$this->url.(($counter - 1) * $this->perpage).'">'.$counter.'</a> ';
					if ( $counter == 1 && $current_page > 1 + $offset ) {
						$ret .= '... ';
					}
				}
				$counter++;
			}
			$next = $this->current + $this->perpage;
			if ( $this->total > $next ) {
				$ret .= '<a href="'.$this->url.$next.'"><u>&raquo;</u></a> ';
			}
		}
		return $ret;
	}

	/**
	 * Create a navigational dropdown list
	 *
	 * @param   boolean     $showbutton Show the "Go" button?
	 * @return  string
	 **/
	function renderSelect($showbutton = false)
	{
		if ( $this->total < $this->perpage ) {
			return;
		}
		$total_pages = ceil($this->total / $this->perpage);
		$ret = '';
		if ( $total_pages > 1 ) {
   			$ret = '<form name="pagenavform">';
			$ret .= '<select name="pagenavselect" onchange="location=this.options[this.options.selectedIndex].value;">';
			$counter = 1;
			$current_page = intval(floor(($this->current + $this->perpage) / $this->perpage));
			while ( $counter <= $total_pages ) {
				if ( $counter == $current_page ) {
					$ret .= '<option value="'.$this->url.(($counter - 1) * $this->perpage).'" selected="selected">'.$counter.'</option>';
				} else {
					$ret .= '<option value="'.$this->url.(($counter - 1) * $this->perpage).'">'.$counter.'</option>';
				}
				$counter++;
			}
			$ret .= '</select>';
			if ($showbutton) {
				$ret .= '&nbsp;<input type="submit" value="'._GO.'" />';
			}
			$ret .= '</form>';
		}
		return $ret;
	}

	/**
	 * Create navigation with images
	 *
	 * @param   integer     $offset
	 * @return  string
	 **/
	function renderImageNav($offset = 4)
	{
		if ( $this->total < $this->perpage ) {
			return;
		}
		$total_pages = ceil($this->total / $this->perpage);
		$ret = '';
		if ( $total_pages > 1 ) {
   			$ret = '<table><tr>';
			$prev = $this->current - $this->perpage;
			if ( $prev >= 0 ) {
				$ret .= '<td class="pagneutral"><a href="'.$this->url.$prev.'">&lt;</a></td><td><img src="'.XOOPS_URL.'/images/blank.gif" width="6" alt="" /></td>';
			} else {
				$ret .= '<td class="pagno"></a></td><td><img src="'.XOOPS_URL.'/images/blank.gif" width="6" alt="" /></td>';
			}
			$counter = 1;
			$current_page = intval(floor(($this->current + $this->perpage) / $this->perpage));
			while ( $counter <= $total_pages ) {
				if ( $counter == $current_page ) {
					$ret .= '<td class="pagact"><b>'.$counter.'</b></td>';
				} elseif ( ($counter > $current_page-$offset && $counter < $current_page + $offset ) || $counter == 1 || $counter == $total_pages ) {
					if ( $counter == $total_pages && $current_page < $total_pages - $offset ) {
						$ret .= '<td class="paginact">...</td>';
					}
					$ret .= '<td class="paginact"><a href="'.$this->url.(($counter - 1) * $this->perpage).'">'.$counter.'</a></td>';
					if ( $counter == 1 && $current_page > 1 + $offset ) {
						$ret .= '<td class="paginact">...</td>';
					}
				}
				$counter++;
			}
			$next = $this->current + $this->perpage;
			if ( $this->total > $next ) {
				$ret .= '<td><img src="'.XOOPS_URL.'/images/blank.gif" width="6" alt="" /></td><td class="pagneutral"><a href="'.$this->url.$next.'">&gt;</a></td>';
			} else {
				$ret .= '<td><img src="'.XOOPS_URL.'/images/blank.gif" width="6" alt="" /></td><td class="pagno"></td>';
			}
			$ret .= '</tr></table>';
		}
		return $ret;
	}
}

?>