<?php 
$Code = '解密代码'; // base64编码 
$File = 'test.php';//解码后保存的文件 
$Temp = base64_decode($Code); 
$temp = gzinflate($Temp); 
$FP = fopen($File,"w"); 
fwrite($FP,$temp); 
fclose($FP); 
echo "解密成功！"; 
?>

$code = '解密代码'; // 你的txt的内容全部粘贴过来

do {

    $code = str_replace('eval', '$code =', $code);
    try{
        eval($code);
    } catch (Exception $e) {
        echo 'errro : ' . $code;
        echo $e->getMessage();
        break;
    }

    $code = trim($code, '<>?php');
// 这里也可以用 strpos($code, 'eval')
}while(substr(trim($code), 0, 4) == 'eval');

echo $code;