public ExtensionInfoModel(ViewModel parent, string extension)
        {
            Parent    = parent;
            Extension = extension;
            if (Extension.Equals("excel"))
            {
                Extension = "xlsx";
            }

            var fileformat = FileFormat.GetByExtension(Extension.ToLower());

            Name        = fileformat.Name;
            Description = fileformat.Description;
            Url         = fileformat.FileFormatComUrl;
        }