using?System;
using?System.Collections.Generic;
using?System.Linq;
using?System.Text;
using?System.Threading.Tasks;
using?System.Security.Cryptography;
using?System.IO;

namespace?AESEncrypt
{
????class?AES_EnorDecrypt
????{
????????//定義默認密鑰
????????private?static?byte[]?_aesKeyByte?=?{?0x12?0x34?0x56?0x78?0x90?0xAB?0xCD?0xEF?0x12?0x34?0x56?0x78?0x90?0xAB?0xCD?0xEF?};
????????private?static?string?_aesKeyStr?=?Encoding.UTF8.GetString（_aesKeyByte）;

????????///?

????????///?隨機生成密鑰，默認密鑰長度為32，不足在加密時自動填充空格
????????///?

????????///?密鑰長度
????????///?
????????public?static?string?GetIv（int?n）
????????{
????????????string?s?=?“abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ“;
????????????char[]?arrChar?=?new?char[s.Length];
????????????for?（int?i?=?0;?i?????????????{
????????????????arrChar[i]?=?Convert.ToChar（s.Substring（i?1））;
????????????}
????????????StringBuilder?num?=?new?StringBuilder（）;
????????????Random?rnd?=?new?Random（DateTime.Now.Millisecond）;
????????????for?（int?i?=?0;?i?????????????{
????????????????num.Append（arrChar[rnd.Next（0?arrChar.Length）].ToString（））;
????????????}
????????????_aesKeyByte?=?Encoding.UTF8.GetBytes（num.ToString（））;
????????????return?_aesKeyStr?=?Encoding.UTF8.GetString（_aesKeyByte）;
????????}

????????///?

????????///?AES加密，針對文本類文件
????????///?

????????///?被加密的明文
????????///?密鑰
????????///?密鑰向量
????????///?密文
????????public?static?string?AESEncrypt（string?Data?string?Key?string?Vector）
????????{
????????????byte[]?plainBytes?=?Encoding.UTF8.GetBytes（Data）;
????????????byte[]?bKey?=?new?byte[32];
????????????Array.Copy（Encoding.UTF8.GetBytes（Key.PadRight（bKey.Length））?bKey?bKey.Length）;
????????????byte[]?bVector?=?new?byte[16];
????????????Array.Copy（Encoding.UTF8.GetBytes（Vector.PadRight（bVector.Length））?bVector?bVector.Length）;
????????????byte[]?Cryptograph?=?null;//加密后的密文
????????????Rijndael?Aes?=?Rijndael.Create（）;
????????????try
????????????{
????????????????using?（MemoryStream?Memory?=?new?MemoryStream（））
????????????????{
????????????????????//把內存流對象包裝成加密流對象
????????????????????using?（CryptoStream?Encryptor?=?new?CryptoStream（Memory?Aes.CreateEncryptor（bKey?bVector）?CryptoStreamMode.Write））
????????????????????{
????????????????????????Encryptor.Write（plainBytes?0?plainBytes.Length）;
????????????????????????Encryptor.FlushFinalBlock（）;
????????????????????????Cryptograph?=?Memory.ToArray（）;
????????????????????}
????????????????}
????????????}
????????????catch
????????????{
????????????????Cryptograph?=?null;
????????????}
????????????return?Convert.Tobase64String（Cryptograph）;
????????}

????????///?

????????///?AES加密，任意文件
????????///?

????????///?