api.cs

[HttpGet]
[Route("Check")]
public List<IncorrectWordModel> Check(string text, string language = "en_US")
{
    if (text == null)
        return null;

    // create a new spell checking engine
    TXTextControl.Proofing.TXSpell spell = new TXTextControl.Proofing.TXSpell();
    spell.Create();

    TXTextControl.Proofing.OpenOfficeDictionary dict = 
        new OpenOfficeDictionary(@"Dictionaries\en_US.dic");
    spell.Dictionaries.Add(dict);

    spell.Check(text, new System.Globalization.CultureInfo(language));

    List<IncorrectWordModel> lIncorrectWords = new List<IncorrectWordModel>();

    var incorrectWords = spell.IncorrectWords;

    if (incorrectWords == null)
        return null;

    foreach (IncorrectWord word in incorrectWords)
    {
        lIncorrectWords.Add(new IncorrectWordModel()
        {
            Text = word.Text,
            Index = word.Index,
            IsDuplicate = word.IsDuplicate,
            Length = word.Length,
            Start = word.Start
        });
    }

    return lIncorrectWords;
}