简单的PHP日历算法

                  /**  
  * 日历  
  *  
  * Copyright(c) 2007 by 陈毅鑫(深空). All rights reserved  
  * To contact the author write to
[color=]{@link
[color=]
mailto:[email protected]}  
  * @author 陈毅鑫(深空)  
  */
if (function_exists('date_default_timezone_set')) {  
     date_default_timezone_set('Asia/Chongqing');  
}  
$date = isset($_GET['date']) ? $_GET['date'] : date('Y-m-d');  
$date = getdate(strtotime($date));  
$end = getdate(mktime(0, 0, 0, $date['mon'] + 1, 1, $date['year']) - 1);
$start = getdate(mktime(0, 0, 0, $date['mon'], 1, $date['year']));  
$pre = date('Y-m-d', $start[0] - 1);  
$next = date('Y-m-d', $end[0] + 86400);  
$html = '[table]';  
$html .= '[tr]';  
$html .= '[td][url=' . $PHP_SELF . '?date=' . $pre . ']-[/url][/td]';  
$html .= '[td]' . $date['year'] . ';' . $date['month'] . '[/td]';  
$html .= '[td][url=' . $PHP_SELF . '?date=' . $next . ']+[/url][/td]';  
$html .= '[/tr]';  
$arr_tpl = array(0 => '', 1 => '', 2 => '', 3 => '', 4 => '', 5 => '', 6 => '');
$date_arr = array();  
$j = 0;  
for ($i = 0; $i