给文件加密的技术很多，其中又分为不同等级，以适合不同场合的需要。这里给出最简单的文件加密技术，即采用文件逐字节与密码异或方式对文件进行加密，当解密时，只需再运行一遍加密程序即可。



下面是一个实例程序，能对任意一个文件进行加密，密码要求用户输入，限8位以内（当然你可以再更改）。程序有很好的容错设计，这是我们应该学习的-Give a lot of file encryption technology, which is divided into different levels to fit the needs of different occasions. Give here the most simple file encryption technology, which adopts the document-by-byte XOR with the password encrypted on the file, when decrypted, simply re-run again encryption procedures. The following is an example of the procedure, any document can be encrypted, password, require users to input, limited to eight days (of course you can change). Procedures have a very good fault-tolerant design, that is what we should study the