用php实现像JSP,ASP里Application那样的全局变量

<?php 
/** 
 * 功能：实现像JSP,ASP里Application那样的全局变量 
 * author: [url]www.itzg.net[/url] 
 * version: 1.0 
 * 版权：如许转载请保留版权声明 
 */ 
/*+----------------example---------------------- 
require_once("Application.php"); 

$arr = array(0=>"Hi",1=>"Yes"); 
$a = new Application(); 
$a->setValue("t1","arui"); 
$a->setValue("arr",$arr); 
$u = $a->getValue(); 
---------------------------------------------+*/ 
class Application 
{ 
 /**保存共享变量的文件*/ 
 var $save_file    = 'Application/Application'; 
 /**共享变量的名称*/ 
 var $application  = null; 
 /**序列化之后的数据*/ 
  var $app_data    = ''; 
  /**是否已经做过setValue的操作 防止频繁写文件操作*/ 
  var $__writed    = false; 

  /** 
   * 构造函数 
   */ 
  function Application() 
  { 
   $this->application = array(); 
  } 
  /** 
   * 设置全局变量 
   * @param string $var_name 要加入到全局变量的变量名 
   * @param string $var_value 变量的值 
   */ 
  function setValue($var_name,$var_value) 
  { 
   if (!is_string($var_name) || empty($var_name)) 
    return false; 
   if ($this->__writed) 
   { 
    $this->application[$var_name] = $var_value; 
    return; 
   } 
   $this->application = $this->getValue(); 
   if (!is_array($this->application)) 
    settype($this->application,"array"); 
   $this->application[$var_name] = $var_value; 
   $this->__writed = true; 
      $this->app_data = @serialize($this->application);     
      $this->__writeToFile(); 
  } 
 /** 
  * 取得保存在全局变量里的值 
  * @return array 
  */ 
 function getValue() 
 { 
     if (!is_file($this->save_file)) 
         $this->__writeToFile(); 
     return @unserialize(@file_get_contents($this->save_file)); 
 } 
 /** 
  * 写序列化后的数据到文件 
  * @scope private 
  */ 
 function __writeToFile() 
 { 
  $fp = @fopen($this->save_file,"w"); 
  @fwrite($fp,$this->app_data); 
  @fclose($fp); 
 } 
} 

?>