The ASP.NET Rich Text Editor (ASPxRichEdit) delivers built-in spell checking support, including the type-as-you-go error detection. This demo shows how a document's spelling can be checked and corrected within the RichEdit.
You can use the Settings.SpellChecker property to define the spell checking availability and the main spelling options (such as the selected culture and paths to alphabet, grammar and dictionary files).
The spell-checking functionality exposed by the RichEdit is provided by the ASPxSpellChecker control. To learn more about the capabilities of the DevExpress ASP.NET Spell Checker, refer to its demos.