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ASPxRichEdit - How to open SpellChecker dialog via Ribbon

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ASPxRichEdit provides built-in spell checking support, including the type-as-you-go error detection. End-users can correct a misspelled word in the Spelling dialog. It can be opened using the corresponding context menu's item when a cursor is over the misspelled word. This dialog allows a user to select spelling suggestions (they are also displayed in the context menu), change or ignore the error once or in all cases, and add a new word to the dictionary. You can also invoke the Spelling dialog using the client-side openSpellingDialog command. 

In this example, ASPxRichEdit includes a custom ribbon button: clicks on this item are processed using the client-side CustomCommandExecuted event. The event handler identifies the custom item via a command name and executes the openSpellingDialog command.