Aes文件的加密和加密

 这是button的核心代码：
 private void Button_Click(object sender, RoutedEventArgs e)
        {
            string str1 = "明文.txt";
            string str2 = "密文.txt";
            if (p1.Password.Length<5)
            {
                MessageBox.Show("密码不能低于5位");
                return;
            }
            byte[] key, iv;
            aes.GenKeyIV(p1.Password, out key, out iv);
            string ss = "";
            FileStream fs = new FileStream(str1, FileMode.Open, FileAccess.Read);
            StreamReader sr = new StreamReader(fs);
            ss = sr.ReadToEnd();
            fs.Close();
            sr.Close();
            a1.Text = "原始字符串：" + ss;
            byte[] data1 = aes.EncryptString(str1, str2, key, iv);
            string encryptedString = Convert.ToBase64String(data1);
            a1.Text += "\n加密后的字符串：" + encryptedString;
            byte[] data2 = Convert.FromBase64String(encryptedString);
            string s = aes.DescrptString(data2, key, iv);
            a1.Text += "\n解密后的字符串：" + s;
        }

创建一个aes类，核心代码为：
public static byte[] EncryptString(string str1, string str2, byte[] key, byte[] iv)  //使用AES算法加密字符串
        {
            string ss = "";
            FileStream fs = new FileStream(str1, FileMode.Open, FileAccess.Read);
            StreamReader sr = new StreamReader(fs);
            ss = sr.ReadToEnd();
            fs.Close();
            sr.Close();

            FileStream fs1 = new FileStream(str2, FileMode.Create, FileAccess.Write);
            using (Aes aesAlg = Aes.Create())
            {
                ICryptoTransform encryptor = aesAlg.CreateEncryptor(key, iv);
                CryptoStream cs = new CryptoStream(fs1, encryptor, CryptoStreamMode.Write);
                using (StreamWriter sw = new StreamWriter(cs))
                {
                    sw.Write(ss);
                }
                cs.Close();
                fs1.Close();
            }
            fs1 = new FileStream(str2, FileMode.Open, FileAccess.Read);
            BinaryReader br = new BinaryReader(fs1);
            byte[] encrypted = br.ReadBytes(10240);
            br.Close();
            fs1.Close();
            return encrypted;
        }
        public static string DescrptString(byte[] data, byte[] key, byte[] iv)  //使用AES算法解密字符串
        {
            string str = "";
            using (Aes aesAlg = Aes.Create())
            {
                ICryptoTransform decryptor = aesAlg.CreateDecryptor(key, iv);
                MemoryStream ms = new MemoryStream(data);
                CryptoStream cs = new CryptoStream(ms, decryptor, CryptoStreamMode.Read);
                using (StreamReader sr = new StreamReader(cs))
                {
                    str = sr.ReadToEnd();
                }
                cs.Close();
                ms.Close();
            }
            return str;
        }
        public static void GenKeyIV(string password, out byte[] key, out byte[] iv)   //根据提供的密码生成key和IV
        {
            using (Aes aes = Aes.Create())
            {
                key = new byte[aes.Key.Length];
                byte[] pwdBytes = Encoding.UTF8.GetBytes(password);
                for (int i = 0; i < pwdBytes.Length; i++)
                {
                    key[i] = pwdBytes[i];
                }
                iv = new byte[aes.IV.Length];
                for (int i = 0; i < pwdBytes.Length; i++)
                {
                    iv[i] = pwdBytes[i];
                }
            }
        }
        public static void GenKeyIV(out byte[] key, out byte[] iv)   //随机生成Key和IV
        {
            using (Aes aes = Aes.Create())
            {
                key = aes.Key;
                iv = aes.IV;
            }
        }