private void ActOK_Click(System.Object sender, System.EventArgs e)
{
// ----- The start city is required.
if (StartCity.Text.Trim().Length == 0)
{
MessageBox.Show("Please provide a start city.");
StartCity.Focus();
return;
}
// ----- The end city is required.
if (EndCity.Text.Trim().Length == 0)
{
MessageBox.Show("Please provide an end city.");
EndCity.Focus();
return;
}
// ----- The cities can't be the same.
if (StartCity.Text.Trim().ToUpper() == EndCity.Text.Trim().ToUpper())
{
MessageBox.Show("The start and end cities must be different.");
EndCity.Focus();
return;
}
// ----- Success.
this.DialogResult = DialogResult.OK;
}
public override string ToString() => StartCity.ToString() + "-" + EndCity.ToString();