private async void Btn_Decrypt_Click(object sender, EventArgs e) { if (Rdb_RsaEncrypt.Checked) { var Dec = await Rsa.DecryptAsync(Txt_PrivateKey.Text, Txt_CipherText.Text); Txt_PlainText.Text = Dec; } else { try { AESCryptography Aes = new AESCryptography(); var Dec = Aes.DecryptAsync(Txt_PublicKey.Text, Txt_CipherText.Text); Txt_PlainText.Text = Dec; } catch (Exception ex) { MessageBox.Show(ex.GetErrorMessage()); } } }