演示完整的对称、非对称、摘要算法。

参照提示：其中有屏幕的和弹出提示。用RSA加密字符串前16个字节

用MD5签名加密后的文件,并可用MD5检验文件是否被篡改过-complete demonstration of symmetric, asymmetric, the digest algorithm. Cross-reference : the screen and a pop-up prompt. Using RSA encryption string before 16 byte encryption with MD5 signature of documents, MD5 test available and whether the document was altered