php代码加密

<?php  
 function encode_file_contents($filename) {  
     
     $type=strtolower(substr(strrchr($filename,'.'),1));  
     if ('php' == $type && is_file($filename) && is_writable($filename)) { // 如果是PHP文件 并且可写 则进行压缩编码  
         $contents = file_get_contents($filename); // 判断文件是否已经被编码处理  
         $contents = php_strip_whitespace($filename);   

         // 去除PHP头部和尾部标识  
         $headerPos = strpos($contents,'<?php');  
         $footerPos = strrpos($contents,'?>');  
         $contents = substr($contents, $headerPos + 5, $footerPos - $headerPos);  
         $encode = base64_encode(gzdeflate($contents)); // 开始编码  
         $encode = '<?php'."\n eval(gzinflate(base64_decode("."'".$encode."'".")));\n\n?>";   

         return file_put_contents($filename, $encode);  
     }  
     return false;  
 }   

 //调用函数  
 $filename = './test.php';  
encode_file_contents($filename);  
 echo "OK,加密完成！";
 ?>