使用Newtonsoft将DataTable转Json

    /// <summary>
    /// DataTable转Json
    /// </summary>
    /// <param name="dt"></param>
    /// <returns></returns>
    public static string ToJson(this DataTable dt)
    {
       return Newtonsoft.Json.JsonConvert.SerializeObject(dt, Newtonsoft.Json.Formatting.None, new Newtonsoft.Json.Converters.DataTableConverter());
    }