Web Listing 1: C# Code for Form1.cs

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

namespace HierarchicalReport
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            // Connection string; substitute DataSource with your server name
            string cnString = "Data Source=(local);Initial
                              Catalog=AdventureWorks;Integrated Security=SSPI;";

            // Declare connection, command, and other related objects
            SqlConnection conReport = new SqlConnection(cnString);
            SqlCommand cmdReport = new SqlCommand();
            SqlDataReader drReport;
            DataSet dsReport = new dsEmployee();

            try
            {
                //open connection
                conReport.Open();

                // Prepare connection, get the data through the reader, and populate DataSet
                cmdReport.CommandType = CommandType.Text;
                cmdReport.Connection = conReport;
                cmdReport.CommandText = @"SELECT Person.Contact.FirstName + 
                     Person.Contact.LastName + ' / ' +  HumanResources.Employee.Title
                     AS EmployeeName, " + "HumanResources.Employee.ManagerID,
                     HumanResources.Employee.EmployeeID " + "FROM HumanResources.Employee
                     INNER JOIN Person.Contact ON " + "HumanResources.Employee.ContactID 
                     = Person.Contact.ContactID";

                // Read data from command object
                drReport = cmdReport.ExecuteReader();

                // Load data directly from the reader to the DataSet
                dsReport.Tables[0].Load(drReport);

                // Close reader and connection
                drReport.Close();
                conReport.Close();

                // Prepare report for preview
                rptHierarchical rptHierarchicalReport = new rptHierarchical();
                rptHierarchicalReport.SetDataSource(dsReport.Tables[0]);
                crystalReportViewer1.DisplayGroupTree = false;
                crystalReportViewer1.ReportSource = rptHierarchicalReport;
            }
            catch (Exception ex)
            {
                // Display generic error message to user
                MessageBox.Show(ex.Message);
            }
            finally
            {
                // Check whether connection is still open; if so, attempt to close it
                if (conReport.State == ConnectionState.Open)
                {
                    conReport.Close();
                }
            }
        }
    }
}