private void PopulateTree()
        {

            // Get the data
            List<CompanyEntity> companyList = this.BuildCompanyList();
            List<CustomerEntity> customerList = this.BuildCustomerList();

            List<DataTreeNode> nodeList = new List<DataTreeNode>();
            foreach (CompanyEntity company in companyList)
            {

                // Build the company node
                DataTreeNode companyNode = new DataTreeNode();
                nodeList.Add(companyNode);

                companyNode.Key = company.CompanyId.ToString();
                companyNode.Value = company.CompanyId.ToString();
                companyNode.Text = company.Description;

                // Build the customer node list
                List<CustomerEntity> companyCustomerList = customerList.FindAll(
                    delegate(CustomerEntity p)
                    {
                        return p.CompanyId == company.CompanyId;
                    }
                );

                companyCustomerList.Sort(
                    delegate(CustomerEntity p1, CustomerEntity p2)
                    {
                        return p1.Name.CompareTo(p2.Name);
                    }
                );

                List<DataTreeNode> customerCollection = new List<DataTreeNode>();
                foreach (CustomerEntity customer in companyCustomerList)
                {

                    DataTreeNode customerNode = new DataTreeNode();
                    customerNode.Key = customer.CustomerId.ToString();
                    customerNode.Value = customer.CustomerId.ToString();
                    customerNode.Text = customer.Name;
                   
                    customerCollection.Add(customerNode);

                }

                companyNode.Nodes.AddRange(customerCollection.ToArray());

            }

            // Display the data
            this.WebDataTree1.Nodes.AddRange(nodeList.ToArray());

        }