/// <summary>
/// Verification is handled by this form rather than the expression editor, as the expression editor is just for the
/// expression rather than the equation object as a whole.
/// </summary>
private void inputWindow_Verify(object sender, ExpressionVerificationEventArgs e)
{
try
{
e.Equation.Parse();
}
catch (ParseException ex)
{
MessageBox.Show(ex.Message, "Equation Parse Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
if (ex.Cause != null)
{
e.Cursor.Expression = ex.Cause.Parent;
e.Cursor.Index = ex.Cause.IndexInParent();
}
e.Failure = true;
}
}
/// <summary>
/// Verifies that the entered expression is valid by iterating through all of the event
/// handlers for the <see cref="Graphmatic.ExpressionEditor.Verify"/> event and checking that
/// the <see cref="Graphmatic.ExpressionVerificationEventArgs.Failure"/> property is not
/// set to true. If the property remains false, then this method returns true; this method
/// returns false otherwise.
/// </summary>
/// <returns>Returns whether the expression verification was successful.</returns>
private bool VerifyExpression()
{
EventHandler <ExpressionVerificationEventArgs> eventHandler = Verify;
if (eventHandler != null)
{
var multicastHandlers = eventHandler.GetInvocationList();
var eventArgs = new ExpressionVerificationEventArgs()
{
Cursor = expressionDisplay.ExpressionCursor,
Failure = false,
Equation = Equation
};
foreach (EventHandler <ExpressionVerificationEventArgs> multicastHandler in multicastHandlers)
{
multicastHandler(this, eventArgs);
if (eventArgs.Failure)
{
return(false);
}
}
}
return(true);
}