一个很好的cost算法对文件夹、文档、图片、视频等的加解密可以有效的保证文件的安全-cost of a good algorithm for folders, documents, pictures, video, the encryption and decryption can effectively guarantee the safety document

通过DES算法实现对文件的加解密，文件夹的加解密，可实现另存的功能-An application about keep the filter safty