System.Text.RegularExpressions.RegexCharClass.AddCategoryFromName C# (CSharp) Method

        internal void AddCategoryFromName(string categoryName, bool invert, bool caseInsensitive, string pattern) {

            object cat = _definedCategories[categoryName];
            if (cat != null) {
                string catstr = (string) cat;

                if (caseInsensitive) {
                    if (categoryName.Equals("Lu") || categoryName.Equals("Lt"))
                        catstr = /*catstr +*/ (string) _definedCategories["Ll"];
                }
            
                if (invert)
                    catstr = NegateCategory(catstr); // negate the category

                _categories.Append((string) catstr);
            }
            else
                AddSet(SetFromProperty(categoryName, invert, pattern));
        }

        internal static RegexCharClass CreateFromCategory(string categoryName, bool invert, bool caseInsensitive, string pattern)
        {
            RegexCharClass class2 = new RegexCharClass();

            class2.AddCategoryFromName(categoryName, invert, caseInsensitive, pattern);
            return(class2);
        }