#region using Directives
using System;
using System.Data;    //Use ADO.NET namespace
using System.Data.SqlClient;  //Use SQL Server data provider namespace
using System.Collections.Generic;
using System.Linq;
using System.Text;
#endregion
namespace DataRelation
{
    class Program
    {
        static void Main(string[] args)
        {
            SqlConnection thisConnection = new SqlConnection("user id=pos;PWD=PO$$IBLE;Server=192.168.2.44;DataBase=gdbranch;TimeOut=30;");
            SqlDataAdapter thisAdapter = new SqlDataAdapter(
                "SELECT CustomerID,Customername from Customers", thisConnection);
            SqlCommandBuilder thisBuilder = new SqlCommandBuilder(thisAdapter);
            DataSet thisDataSet = new DataSet();
            SqlDataAdapter custAdapter=new SqlDataAdapter(
                "Select * from customers",thisConnection);
            SqlDataAdapter orderAdapter=new SqlDataAdapter(
                "SELECT * FROM Orders",thisConnection);
            custAdapter.Fill(thisDataSet,"Customers");
            orderAdapter.Fill(thisDataSet,"Orders");

            DataRelation custOrderRel = thisDataSet.Relations.Add("CustOrders",
                thisDataSet.Tables["Customers"].Columns["CustomerID"],
                thisDataSet.Tables["Orders"].Columns["CustomerID"]);
            foreach(DataRow custRow in thisDataSet.Tables["Customers"].Rows)
            {
                Console.WriteLine("Customer ID:"+custRow["CustomerID"]+
                    "Name:"+custRow["CompanyName"]);
                foreach (DataRow orderRow in custRow.GetChildRows(custOrderRel))
                {
                    Console.WriteLine(" Order ID:"+orderRow["OrderID"]);
                }
            }
            thisConnection.Close();
            Console.Write("Program finished,press Enter/Return to continue:");
            Console.ReadLine();

        }
    }
}

DataRelation custOrderRel = thisDataSet.Relations.Add("CustOrders",
                thisDataSet.Tables["Customers"].Columns["CustomerID"],
                thisDataSet.Tables["Orders"].Columns["CustomerID"]);