using System;

using System.Data;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

        DataTable dt = new DataTable();

        dt.Clear();

        dt.Columns.Add("ID", typeof(int));

        dt.Columns.Add("BatchCount", typeof(int));

        for (var i = 1; i < 101; i++)

        {

            DataRow row = dt.NewRow();

            row["ID"] = i;

            row["BatchCount"] = 20;

            dt.Rows.Add(row);

        }

​

        var result = GetBatchCount(dt);

        Console.WriteLine(result);

    }

​

    private static long GetBatchCount(DataTable batches)

    {

        long retCount = 0;

        if (batches != null && batches.Rows.Count > 0)

        {

            retCount = Convert.ToInt64(batches.Compute("sum(BatchCount)", ""));

        }

​

        return retCount;

    }

}