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！";
  ?>