private void ValidateTextInput(TextBox textBox, out double sideLength)
{
// Allow text boxes that are empty or that contain only a single decimal.
if (string.IsNullOrEmpty(textBox.Text) || textBox.Text == ".")
{
sideLength = 0;
}
// If current input is not a valid number, clear text box and display invalid input error.
else if (!double.TryParse(textBox.Text, out sideLength))
{
messageText.Text = ERR_INVALID_INPUT;
// Temporarily disable events to prevent firing when clearing the text box.
DisableTextBoxEvents();
textBox.Clear();
EnableTextBoxEvents();
return;
}
// If any inputs are blank, display instructions.
if (string.IsNullOrEmpty(sideATextBox.Text) || string.IsNullOrEmpty(sideBTextBox.Text) || string.IsNullOrEmpty(sideCTextBox.Text))
{
messageText.Text = INSTRUCTIONS;
return;
}
try
{
var info = TriangleChecker.GetTriangleStats(_sideA, _sideB, _sideC);
// Side lenghts make a valid triangle! Display the triangle type.
messageText.Text = GetTriangleMessage(info);
}
catch (ArgumentException)
{
// One or more side lengths are not valid; display invalid input error.
messageText.Text = ERR_INVALID_INPUT;
}
catch (InvalidTriangleException)
{
// Side lengths do not make a valid triangle; display invalid triangle error.
messageText.Text = ERR_INVALID_TRIANGLE;
}
}