common/persistent.class.php

<?
# Base class to implement object persistence using serialize and unserialize

class persistent
{
   var $filename;
       
   /**********************/
   function Persistent($filename)
   {
       $this->filename = $filename;
       if(!file_exists($this->filename)) $this->save();
   }
   /**********************/
   function save()
   {
       if($f = @fopen($this->filename,"w"))
       {
           if(@fwrite($f,serialize(get_object_vars($this))))
           {
               @fclose($f);
           }
           else die("Could not write to file ".$this->filename." at Persistant::save");
       } else die("Could not open file ".$this->filename." for writing, at Persistant::save");
       
   }
   /**********************/
   function open()
   {
       $vars = unserialize(file_get_contents($this->filename));
       foreach($vars as $key=>$val)
       {            
           eval("$"."this->$key = $"."vars['"."$key'];");
       }
   }
   /**********************/
}

?>