using System;

using System.Collections.Generic;

using System.Data;

using System.Linq;

using Newtonsoft.Json;

public class Program

{

    public static void Main()

    {

        DataTable dataTable = new DataTable();

        dataTable.Columns.Add("Address");

        dataTable.Columns.Add("BodyOverride");

        dataTable.Columns.Add("ChannelType");

        dataTable.Rows.Add("+1713XXXXXXX", "sent", "SMS");

        dataTable.Rows.Add("+1832XXXXXXX", "this is a text from PINPOINT", "SMS");

​

        var payload = new Payload

        {

            Addresses = dataTable.Rows

                .Cast<DataRow>()

                .ToDictionary(row => (string)row["Address"],

                              row => new Item

                              {

                                  BodyOverride = (string)row["BodyOverride"],

                                  ChannelType = (string)row["ChannelType"]

                              })

        };

​

        string json = JsonConvert.SerializeObject(payload, Formatting.Indented);

        Console.WriteLine(json);

    }

}

​

public class Payload

{

    public Dictionary<string, Item> Addresses { get; set; }

}

​

public class Item

{

    public string BodyOverride { get; set; }

    public string ChannelType { get; set; }

}

​