private string GetPropertyName(DictionaryEntry entry)
        {
            if (entry.get_Key() is IConvertible)
            {
                return(Convert.ToString(entry.get_Key(), CultureInfo.get_InvariantCulture()));
            }
            string result;

            if (JsonSerializerInternalWriter.TryConvertToString(entry.get_Key(), entry.get_Key().GetType(), out result))
            {
                return(result);
            }
            return(entry.get_Key().ToString());
        }