Set the Code to highlighted in blue, code to highlighted

Set the Code to highlighted in blue, code to highlighted

The following method highlights the configured keywords and takes into account the effects of annotations and strings. Therefore, it can be used in the future.

        private static void ColorizeCode(RichTextBox rtb)        {            string[] keywords = {"as", "do", "if", "in", "is", "for", "int", "new", "out", "ref", "try", "base",                                "bool", "byte", "case", "char", "else", "enum", "goto", "lock", "long", "null",                                "this", "true", "uint", "void", "break", "catch", "class", "const", "event", "false",                                "fixed", "float", "sbyte", "short", "throw", "ulong", "using", "where", "while",                                "yield", "double", "extern", "object", "params", "public", "return", "sealed",                                "sizeof", "static", "string", "struct", "switch", "typeof", "unsafe", "ushort",                                "checked", "decimal", "default", "finally", "foreach", "partial", "private",                                "virtual", "abstract", "continue", "delegate", "explicit", "implicit", "internal",                                "operator", "override", "readonly", "volatile",                                "interface", "namespace", "protected", "unchecked",                                "stackalloc",                                "from", "in", "where", "select", "join", "equals", "let", "on", "group", "by",                                "into", "orderby", "ascending", "descending", "var"};            string text = rtb.Text;            rtb.SelectAll();            rtb.SelectionColor = rtb.ForeColor;            foreach (String keyword in keywords)            {                int keywordPos = rtb.Find(keyword, RichTextBoxFinds.MatchCase | RichTextBoxFinds.WholeWord);                while (keywordPos != -1)                {                    int commentPos = text.LastIndexOf("//", keywordPos, StringComparison.OrdinalIgnoreCase);                    int newLinePos = text.LastIndexOf("\n", keywordPos, StringComparison.OrdinalIgnoreCase);                    int quoteCount = 0;                    int quotePos = text.IndexOf("\"", newLinePos + 1, keywordPos - newLinePos, StringComparison.OrdinalIgnoreCase);                    while (quotePos != -1)                    {                        quoteCount++;                        quotePos = text.IndexOf("\"", quotePos + 1, keywordPos - (quotePos + 1), StringComparison.OrdinalIgnoreCase);                    }                    if (newLinePos >= commentPos && quoteCount % 2 == 0)                        rtb.SelectionColor = Color.Blue;                    keywordPos = rtb.Find(keyword, keywordPos + rtb.SelectionLength, RichTextBoxFinds.MatchCase | RichTextBoxFinds.WholeWord);                }            }            rtb.Select(0, 0);        }