Most rich editors implement two types of spell-checking:
- Modal spell checking: Shows the Spelling dialog box and selects each spelling mistake in the document. The user may choose to ignore the mistake, fix it by typing or picking from a list of suggestions, or add the word to a user dictionary.
- As-you-type checking: Highlights spelling mistakes as the user types, typically with a wavy red underline. The user may right-click the mistake in the document to see a menu with options that include ignore, add to dictionary, or pick a suggestion to correct the mistake automatically.
The C1RichTextBox supports both types of spell-checking using the C1SpellChecker component, which is also included in WPF Edition. The C1SpellChecker ships as a separate assembly because it can spell-check other controls as well.