This is just an example project for an Issue that is occuring in the Xceed WPF-Toolkit
The problem is, that with the RtfFormatter (the default Formatter used for RichTextBox.TextFormatter) you'll get a lot of System.FormatExceptions. First, when initializing the Control and after that for every KEYSTROKE. This is not only annoying when developing and testing the Application, but it also slowing down the Application enormously!
Just think of writing a text of 200 words and with every keystroke an Exception will be thrown in the backend (... fetching the Stacktrace and whatnot). Even with the Diagnostic Tools inside of Visual Studio you're able to see, how many resources a simple program will need.
... and this:
To further analyze the Exception, be sure to enable the needed Exception inside the Exception Settings:
Here are simple explanations to the given Examples of the Project:
This is a simple program that uses the RichTextBox from the WpfToolkit as is. So no modifications or anything are made to any of the Properties.
But you'll notice two things:
- An exception will be thrown right when the program starts (The Property
RichTextBox.TextFormatterwill be initilized with the defaultRtfFormatter) - An exception will be thrown for every keystroke, when typing inside the RichTextBox
This is essentially the same as Example 01 but I'm explitely setting the TextFormatter to an instance of RtfFormatter. Nothing changes here, still the same result.
Here I'm setting the TextFormatter to an instance of PlainTextFormatter with the help of a StaticRessource inside MainWindow.xaml.
Here everything will work fine. No exception will be raised when starting the program or typing something inside the RichTextBox. No errors.
Here I'm setting the TextFormatter to an instance of XamlFormatter inside the Contructor after InitializeComponent().
This will raise an exception right when the Program starts (because the TextFormatter will get it's default value (see Example 01)). But after that everything will be alright. No more exceptions when writing text or doing other things.
This is just an example using the default RichTextBox that is implemented within WPF. Here you don't have any way to change a TextFormatter so I didn't change any property.
Here you won't get any errors aswell. Initializing and typing are free from Exceptions.
From the tests covered in the Examples above, you're able to see that something is wrong with the RtfFormatter that is used by default by the RichTextBox in the WpfToolkit by Xceed. It'll throw a lot of System.FormatExceptions when initializing and typing.