Spellcheck a single word in Excel function

Question

This little Excel VBA function always returns false, no what word is passed in.

Function SpellCheck(SomeWord As String)

SpellCheck = Application.CheckSpelli         


        

Answer 1

One pitfall to watch out for is that Application.CheckSpelling will return True for any text that has a character outside the codepage of the language for which you do the spellchecking.

For instance, checking nő in English returns True. Apparently Excel hasn't yet (as of version 2010) fully arrived in the Unicode world.

If that's a problem in your application, you either have to screen out text with characters outside the codepage beforehand, or you can borrow Word's spellchecking function, which doesn't have this bug, for instance like this (adapted from www.vb-tec.de):

    Public Function CheckSpellingWd( _
            ByRef Text As String, _
            Optional ByVal IgnoreUpperCase As Boolean = False, _
            Optional ByVal ReUse As Boolean = True _
        ) As Boolean

        'Reuse Word object on next call
        Static wd As Word.Application

        If Len(Text) > 0 Then
            'create Word object on first call
            If wd Is Nothing Then
            Set wd = New Word.Application
            wd.DisplayAlerts = wdAlertsNone
            End If

            'Do spellcheck
            CheckSpellingWd = wd.CheckSpelling(Text, , IgnoreUpperCase)
        Else
            'Return True on empty string
            CheckSpellingWd = True
        End If
    End Function

Now Unicode is checked fine, and in theory, you can provide a dictionary file path as a parameter to the CheckSpelling function to check in any language you have a dictionary file for:

Application.CheckSpelling(Word, CustomDictionary, IgnoreUppercase, MainDictionary, _
    CustomDictionary2, CustomDictionary3, CustomDictionary4, CustomDictionary5, _
    CustomDictionary6, CustomDictionary7, CustomDictionary8, CustomDictionary9, _
    CustomDictionary10)

In reality however the check is done using the main dictionary of the default language (as set in File/Options/Language) regardless of the dictionary you specify (checked in Word 2010, not sure about previous versions). You can only change that setting manually (and have to restart Word for the change to come into effect).

The default language setting is governed by a registry key. In Office 2010:

HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Common\LanguageResources\InstallLanguage

So in theory, you could automate the language change as well using VBA wrappers to Windows Scripting, WMI or WinAPI to change the registry (and then restart Word), but on Windows 7 with UAC enabled I ran into permission problems, and this is where I gave up on the experiment. I only tried the WinAPI route though.