本文实例讲述了PHP实现的DES加密解密实例。分享给大家供大家参考，具体如下：

<?php

$key = 'very important data';

function jiami($key, $str)

{

  /* Open module, and create IV */

  $td = mcrypt_module_open('des', '', 'ecb', '');

  //$td = mcrypt_module_open(MCRYPT_DES, '', MCRYPT_MODE_CBC, '');

  //$td = mcrypt_module_open('des', '', 'cbc', '');

  $key = substr($key, 0, mcrypt_enc_get_key_size($td));

  $iv_size = mcrypt_enc_get_iv_size($td);

  $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);

  /* Initialize encryption handle */

  if (mcrypt_generic_init($td, $key, $iv) === -1)

  {

    return FALSE;

  }

  /* Encrypt data */

  $c_t = mcrypt_generic($td, $str);

  /* Clean up */

  mcrypt_generic_deinit($td);

  mcrypt_module_close($td);

  return $c_t;

}

function jiemi($key, $str)

{

  /* Open module, and create IV */

  $td = mcrypt_module_open('des', '', 'ecb', '');

  //$td = mcrypt_module_open(MCRYPT_DES, '', MCRYPT_MODE_CBC, '');

  //$td = mcrypt_module_open('des', '', 'cbc', '');

  $key = substr($key, 0, mcrypt_enc_get_key_size($td));

  $iv_size = mcrypt_enc_get_iv_size($td);

  $iv = mcrypt_create_iv($iv_size, MCRYPT_RAND);

  /* Initialize encryption handle */

  if (mcrypt_generic_init($td, $key, $iv) === -1)

  {

    return FALSE;

  }

  /* Reinitialize buffers for decryption */

  $p_t = mdecrypt_generic($td, $str);

  /* Clean up */

  mcrypt_generic_deinit($td);

  mcrypt_module_close($td);

  return trim($p_t);

}

$str = 'hello world!';

echo 'key:' . $key . '<br>';

echo 'str:' . $str . '<br>';

$jiami = jiami($key, $str);

echo '加密:' . $jiami . '<br>';

file_put_contents('jiamiqian.txt', $str);

file_put_contents('jiamihou.txt', $jiami);

$jiemi = jiemi($key, $jiami);

echo '解密:' . $jiemi . '<br>';

希望本文所述对大家PHP程序设计有所帮助。