private void AddButton_Click(object sender, EventArgs e)
 {
     SumAllInput();
     ClearAllInputFields();
     CopyResultToOutputFields();
     CopyResultToClipboard();
     SpeakTheResult(DigitalTimeResult.ToString(CultureInfo.CurrentCulture));
     Time1TextBox.Focus();
 }
 private void ClearAllInputFields()
 {
     Time1TextBox.Clear();
     Time2TextBox.Clear();
     Time3TextBox.Clear();
 }