When you start to modify text in a text object in Microsoft Expression Blend, the spelling checker automatically indicates, with a wavy red underline, all words in the text object that are not included in the current dictionary. You can select from a list of suggested alternative words to replace an underlined word, or you can decide to have the spelling checker ignore all instances of that word.
In the Tools panel, click either Selection or Direct Selection , and then click the text object in which you want to check spelling.
Right-click the text object and then click Edit Text or press F2 to enter text-editing mode.
Right-click any word in the text object that has a wavy red underline to see suggested alternative spellings for the word, and then use one of the following methods:
Click a word in the list to select it to replace the underlined word.
Click Ignore All to stop the spelling checker from underlining instances of the word during that session of checking the spelling.
Not only can you use the spelling checker to check the spelling in your application during design time, but you can also build the spelling checker into your application so that users can check spelling when they enter text in your application during run time.
In the Tools panel, click either Selection or Direct Selection , and then click the user-editable text object for which you want to enable the spelling checker in your application.
Make sure that you are not in text-editing mode by pressing the ESC key.
In the Properties panel, under Miscellaneous, select the SpellCheck.IsEnabled box.