Bind two DataGrids with many to many mapping

   

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
using System.Data.SqlClient;

    public class Form1 : System.Windows.Forms.Form{
      private System.Windows.Forms.DataGrid dataGrid1;
      private System.Data.DataSet dataSet1;
      private System.ComponentModel.Container components = null;

      public Form1() {
        InitializeComponent();
      }
      private void InitializeComponent(){
        this.dataGrid1 = new System.Windows.Forms.DataGrid();
        this.dataSet1 = new System.Data.DataSet();
        ((System.ComponentModel.ISupportInitialize)(this.dataGrid1)).BeginInit();
        ((System.ComponentModel.ISupportInitialize)(this.dataSet1)).BeginInit();
        this.SuspendLayout();

        this.dataGrid1.DataMember = "";
        this.dataGrid1.HeaderForeColor = System.Drawing.SystemColors.ControlText;
        this.dataGrid1.Location = new System.Drawing.Point(0, 0);
        this.dataGrid1.Name = "dataGrid1";
        this.dataGrid1.Size = new System.Drawing.Size(400, 200);
        this.dataGrid1.TabIndex = 0;

        this.dataSet1.DataSetName = "NewDataSet";
        this.dataSet1.Locale = new System.Globalization.CultureInfo("en-US");

        this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
        this.ClientSize = new System.Drawing.Size(400, 196);
        this.Controls.Add(this.dataGrid1);
        this.Name = "Form1";
        this.Text = "Form1";
        this.Load += new System.EventHandler(this.Form1_Load);
        ((System.ComponentModel.ISupportInitialize)(this.dataGrid1)).EndInit();
        ((System.ComponentModel.ISupportInitialize)(this.dataSet1)).EndInit();
        this.ResumeLayout(false);
      }
      [STAThread]
      static void Main() {
        Application.Run(new Form1());
      }

      private void Form1_Load(object sender, System.EventArgs e) {
         string connString = "server=(local)SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
         string qry1 = @"select * from employee ";
         string qry2 = @"select * from order";

         string sql = qry1 + qry2;

         SqlConnection conn = new SqlConnection(connString);
         SqlDataAdapter da = new SqlDataAdapter(sql, conn);
    
         da.TableMappings.Add("Table", "employee");
         da.TableMappings.Add("Table1", "order");
         da.Fill(dataSet1);

         DataRelation dr = new DataRelation(
            "employeeorders",
            dataSet1.Tables[0].Columns["employeeid"], 
            dataSet1.Tables[1].Columns["employeeid"]
            );
         dataSet1.Relations.Add(dr);

         dataGrid1.SetDataBinding(dataSet1, "employees");

      }
    }