编写的DES 对称加解密技术，可随时进行明文密文之间的转换，有需要的朋友可以下载测试！本人目的打算对后台数据库的敏感信息字段用该方法加密，然后用软件权限控制读取，这样即使直接SQL后台取数，也得不到明文数据。-Write DES symmetrical encryption technology, may at any time for conversion between plaintext cipher, friends in need can be download test! I purpose going to the backstage database of sensitive information field with the method of encryption, and then use software to read access control, so even if the SQL backend access directly, also can not get clear data.