/// <summary>
        /// Reads the JSON representation of the object.
        /// </summary>
        /// <param name="reader">The <see cref="JsonReader"/> to read from.</param>
        /// <param name="objectType">Type of the object.</param>
        /// <param name="existingValue">The existing value of object being read.</param>
        /// <param name="serializer">The calling serializer.</param>
        /// <returns>The object value.</returns>
        public override object ReadJson(JsonReader reader, Type objectType, object existingValue, JsonSerializer serializer)
        {
            DataSet ds = new DataSet();

              DataTableConverter converter = new DataTableConverter();

              reader.Read();

              while (reader.TokenType == JsonToken.PropertyName)
              {
            DataTable dt = (DataTable)converter.ReadJson(reader, typeof (DataTable), null, serializer);
            ds.Tables.Add(dt);
              }

              reader.Read();

              return ds;
        }
        /// <summary>
        /// Writes the JSON representation of the object.
        /// </summary>
        /// <param name="writer">The <see cref="JsonWriter"/> to write to.</param>
        /// <param name="value">The value.</param>
        /// <param name="serializer">The calling serializer.</param>
        public override void WriteJson(JsonWriter writer, object value, JsonSerializer serializer)
        {
            DataSet dataSet = (DataSet)value;

              DataTableConverter converter = new DataTableConverter();

              writer.WriteStartObject();

              foreach (DataTable table in dataSet.Tables)
              {
            writer.WritePropertyName(table.TableName);

            converter.WriteJson(writer, table, serializer);
              }

              writer.WriteEndObject();
        }