/// <summary>    ///  This class implements the Execute method of the ISyntaxHighlightService interface to parse and colorize the text.    /// </summary>    public class MySyntaxHighlightServiceCSharp : ISyntaxHighlightService    {        readonly RichEditControl syntaxEditor;        SyntaxColors syntaxColors;        SyntaxHighlightProperties commentProperties;        SyntaxHighlightProperties keywordProperties;        SyntaxHighlightProperties stringProperties;        SyntaxHighlightProperties xmlCommentProperties;        SyntaxHighlightProperties textProperties;        public MySyntaxHighlightServiceCSharp(RichEditControl syntaxEditor)        {            this.syntaxEditor = syntaxEditor;            syntaxColors = new SyntaxColors(UserLookAndFeel.Default);        }        void HighlightSyntax(TokenCollection tokens)        {            commentProperties = new SyntaxHighlightProperties();            commentProperties.ForeColor = syntaxColors.CommentColor;            keywordProperties = new SyntaxHighlightProperties();            keywordProperties.ForeColor = syntaxColors.KeywordColor;            stringProperties = new SyntaxHighlightProperties();            stringProperties.ForeColor = syntaxColors.StringColor;            xmlCommentProperties = new SyntaxHighlightProperties();            xmlCommentProperties.ForeColor = syntaxColors.XmlCommentColor;            textProperties = new SyntaxHighlightProperties();            textProperties.ForeColor = syntaxColors.TextColor;            if (tokens == null || tokens.Count == 0)                return;            Document document = syntaxEditor.Document;            //CharacterProperties cp = document.BeginUpdateCharacters(0, 1);            List<SyntaxHighlightToken> syntaxTokens = new List<SyntaxHighlightToken>(tokens.Count);            foreach (Token token in tokens)            {                HighlightCategorizedToken((CategorizedToken)token, syntaxTokens);            }            document.ApplySyntaxHighlight(syntaxTokens);            //document.EndUpdateCharacters(cp);        }        void HighlightCategorizedToken(CategorizedToken token, List<SyntaxHighlightToken> syntaxTokens)        {            Color backColor = syntaxEditor.ActiveView.BackColor;            TokenCategory category = token.Category;            if (category == TokenCategory.Comment)                syntaxTokens.Add(SetTokenColor(token, commentProperties, backColor));            else if (category == TokenCategory.Keyword)                syntaxTokens.Add(SetTokenColor(token, keywordProperties, backColor));            else if (category == TokenCategory.String)                syntaxTokens.Add(SetTokenColor(token, stringProperties, backColor));            else if (category == TokenCategory.XmlComment)                syntaxTokens.Add(SetTokenColor(token, xmlCommentProperties, backColor));            else                syntaxTokens.Add(SetTokenColor(token, textProperties, backColor));        }        SyntaxHighlightToken SetTokenColor(Token token, SyntaxHighlightProperties foreColor, Color backColor)        {            int paragraphStart = DocumentHelper.GetParagraphStart(syntaxEditor.Document.Paragraphs[token.Range.Start.Line - 1]);            int tokenStart = paragraphStart + token.Range.Start.Offset - 1;            if (token.Range.End.Line != token.Range.Start.Line)                paragraphStart = DocumentHelper.GetParagraphStart(syntaxEditor.Document.Paragraphs[token.Range.End.Line - 1]);            int tokenEnd = paragraphStart + token.Range.End.Offset - 1;            Debug.Assert(tokenEnd > tokenStart);            return new SyntaxHighlightToken(tokenStart, tokenEnd - tokenStart, foreColor);        }        #region #ISyntaxHighlightServiceMembers        public void Execute()        {            string newText = syntaxEditor.Text;            // Determine language by file extension.            string ext = System.IO.Path.GetExtension(syntaxEditor.Options.DocumentSaveOptions.CurrentFileName);            //ParserLanguageID lang_ID = ParserLanguage.FromFileExtension(ext);            //// Do not parse HTML or XML.            //if (lang_ID == ParserLanguageID.Html ||            //    lang_ID == ParserLanguageID.Xml ||            //    lang_ID == ParserLanguageID.None) return;            ParserLanguageID lang_ID = ParserLanguageID.CSharp;            // Use DevExpress.CodeParser to parse text into tokens.            ITokenCategoryHelper tokenHelper = TokenCategoryHelperFactory.CreateHelper(lang_ID);            TokenCollection highlightTokens;            highlightTokens = tokenHelper.GetTokens(newText);            HighlightSyntax(highlightTokens);        }        public void ForceExecute()        {            Execute();        }        #endregion #ISyntaxHighlightServiceMembers    }    /// <summary>    ///  This class provides colors to highlight the tokens.    /// </summary>    public class SyntaxColors    {        static Color DefaultCommentColor { get { return Color.Green; } }        static Color DefaultKeywordColor { get { return Color.Blue; } }        static Color DefaultStringColor { get { return Color.Brown; } }        static Color DefaultXmlCommentColor { get { return Color.Gray; } }        static Color DefaultTextColor { get { return Color.Black; } }        UserLookAndFeel lookAndFeel;        public Color CommentColor { get { return GetCommonColorByName(CommonSkins.SkinInformationColor, DefaultCommentColor); } }        public Color KeywordColor { get { return GetCommonColorByName(CommonSkins.SkinQuestionColor, DefaultKeywordColor); } }        public Color TextColor { get { return GetCommonColorByName(CommonColors.WindowText, DefaultTextColor); } }        public Color XmlCommentColor { get { return GetCommonColorByName(CommonColors.DisabledText, DefaultXmlCommentColor); } }        public Color StringColor { get { return GetCommonColorByName(CommonSkins.SkinWarningColor, DefaultStringColor); } }        public SyntaxColors(UserLookAndFeel lookAndFeel)        {            this.lookAndFeel = lookAndFeel;        }        Color GetCommonColorByName(string colorName, Color defaultColor)        {            Skin skin = CommonSkins.GetSkin(lookAndFeel);            if (skin == null)                return defaultColor;            return skin.Colors[colorName];        }    }

richEditControl1.ReplaceService<ISyntaxHighlightService>(new MySyntaxHighlightServiceCSharp(richEditControl1));

public class CustomSyntaxHighlightService : ISyntaxHighlightService {        #region #parsetokens        readonly Document document;        SyntaxHighlightProperties defaultSettings = new SyntaxHighlightProperties() { ForeColor = Color.Black };        SyntaxHighlightProperties keywordSettings = new SyntaxHighlightProperties() { ForeColor = Color.Blue };        SyntaxHighlightProperties stringSettings = new SyntaxHighlightProperties() { ForeColor = Color.Green };        string[] keywords = new string[] {             "INSERT", "SELECT", "CREATE", "TABLE", "USE", "IDENTITY", "ON", "OFF", "NOT", "NULL", "WITH", "SET" };        public CustomSyntaxHighlightService(Document document) {            this.document = document;        }        private List<SyntaxHighlightToken> ParseTokens() {            List<SyntaxHighlightToken> tokens = new List<SyntaxHighlightToken>();            DocumentRange[] ranges = null;            // search for quotation marks            ranges = document.FindAll("‘", SearchOptions.None);            for (int i = 0; i < ranges.Length / 2; i++) {                tokens.Add(new SyntaxHighlightToken(ranges[i * 2].Start.ToInt(),                     ranges[i * 2 + 1].Start.ToInt() - ranges[i * 2].Start.ToInt() + 1, stringSettings));            }            // search for keywords            for (int i = 0; i < keywords.Length; i++) {                ranges = document.FindAll(keywords[i], SearchOptions.CaseSensitive | SearchOptions.WholeWord);                for (int j = 0; j < ranges.Length; j++) {                    if (!IsRangeInTokens(ranges[j], tokens))                        tokens.Add(new SyntaxHighlightToken(ranges[j].Start.ToInt(), ranges[j].Length, keywordSettings));                }            }            // order tokens by their start position            tokens.Sort(new SyntaxHighlightTokenComparer());            // fill in gaps in document coverage            AddPlainTextTokens(tokens);            return tokens;        }        private void AddPlainTextTokens(List<SyntaxHighlightToken> tokens) {            int count = tokens.Count;            if (count == 0) {                tokens.Add(new SyntaxHighlightToken(0, document.Range.End.ToInt(), defaultSettings));                return;            }            tokens.Insert(0, new SyntaxHighlightToken(0, tokens[0].Start, defaultSettings));            for (int i = 1; i < count; i++) {                tokens.Insert(i * 2, new SyntaxHighlightToken(tokens[i * 2 - 1].End, tokens[i * 2].Start - tokens[i * 2 - 1].End, defaultSettings));            }            tokens.Add(new SyntaxHighlightToken(tokens[count * 2 - 1].End, document.Range.End.ToInt() - tokens[count * 2 - 1].End, defaultSettings));        }        private bool IsRangeInTokens(DocumentRange range, List<SyntaxHighlightToken> tokens) {            for (int i = 0; i < tokens.Count; i++) {                if (range.Start.ToInt() >= tokens[i].Start && range.End.ToInt() <= tokens[i].End)                    return true;            }            return false;        }        #endregion #parsetokens        #region #ISyntaxHighlightServiceMembers        public void ForceExecute() {            Execute();        }        public void Execute() {            document.ApplySyntaxHighlight(ParseTokens());        }        #endregion #ISyntaxHighlightServiceMembers    }    #region #SyntaxHighlightTokenComparer    public class SyntaxHighlightTokenComparer : IComparer<SyntaxHighlightToken> {        public int Compare(SyntaxHighlightToken x, SyntaxHighlightToken y) {            return x.Start - y.Start;        }    }    #endregion #SyntaxHighlightTokenComparer

richEditControl1.ReplaceService<ISyntaxHighlightService>(new CustomSyntaxHighlightService(richEditControl1.Document));