public FormClient()
 {
     InitializeComponent();
     aes      = new Aes_256();
     mySHA256 = SHA256Managed.Create();
     Control.CheckForIllegalCrossThreadCalls = false;
 }
 public void encryptmess(string mess)
 {
     if (mess.Length > 0)
     {
         md5      = new MD5();
         aes      = new Aes_256();
         mySHA256 = SHA256Managed.Create();
         byte[] mess1 = Encoding.UTF8.GetBytes(mess);
         byte[] key1  = mySHA256.ComputeHash(Encoding.ASCII.GetBytes(Convert.ToString(dh.Key_Chung)));
         textBoxkey.Text = Convert.ToBase64String(key1);
         string ivc = getdatime();
         byte[] iv  = create_init_vector(ivc, 2);
         textBoxiv.Text = Convert.ToBase64String(iv);
         byte[]   dayhash  = mySHA256.ComputeHash(Encoding.ASCII.GetBytes(ivc));
         string   encrypt  = aes.EncryptString(mess1, key1, iv, dayhash);
         string[] enc1     = encrypt.Split(';');
         string   mess_md5 = md5.GetMD5(enc1[0] + Convert.ToString(dh.Key_Chung));
         string   messsend = "3;" + encrypt + ";" + ivc + ";" + mess_md5;
         textBoxmessnoise.Text = messsend;
         senddata(messsend);
     }
 }