Using TreeView to Display Records from MDB File in C# 2010

This is a trial to read records from MDB database file using TreeView control. My project is a phone index to display some fields from Customers table in Northwind database file:

CompanyName, ContactName, Address, City, Country and Phone.

My project has one form (frmPhone), this form has following controls:

• TreeView: tvData
• Four TextBoxes:

txtCompany for Company Name, txtAddress for Address, txtCity for City and , txtCountry for Country.

Two Buttons: for load data and exit application.

The Code

There is five procedures:

        private void LoadCustomerData()   // for open the database file
        {
            MyDataFile = Application.StartupPath + @"\DataFile\Northwind.mdb";
            string MyCon = @"provider=microsoft.jet.oledb.4.0;Password="""";data source=" + MyDataFile;
            datCon = new OleDbConnection();
            datCon.ConnectionString = MyCon;
            OleDbCommand cmdSelect = new OleDbCommand();
            OleDbDataAdapter datAdp = new OleDbDataAdapter();
            datSet = new DataSet();
            try
            {
                MyTable = "Customers";
                // Select all fields
                string strSql = "SELECT * FROM " + MyTable + " ORDER BY ContactName";
                cmdSelect.CommandText = strSql;
                cmdSelect.CommandType = CommandType.Text;
                datCon.Open();  // open connection
                cmdSelect.Connection = datCon;
                datAdp.SelectCommand = cmdSelect;
                datAdp.Fill(datSet, MyTable);  // fill dataset
                datCon.Close();
                // if no records then exit:
                int RecCount = this.BindingContext[datSet, MyTable].Count;
                if (RecCount == 0)
                {
                    MessageBox.Show("No records in Customer table file!");
                    return;
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
            }
            SetRootNode();
        }

private void SetRootNode()
        {
            // set root node of TreeView:
            tvData.Nodes.Add("Phone Index");
            tvData.Nodes[0].Tag = "RootDB";
            tvData.Nodes[0].ImageIndex = 0;
            tvData.Nodes[0].SelectedImageIndex = 0;
            //Set Contact Name
            SetContactName();
            //Set Customer Phone
            SetCustPhone();
        }

private void SetContactName()
        {
// set ContactName field as node
            itmNumber = datSet.Tables[MyTable].Rows.Count;
            for (int i = 0; i < itmNumber; i++)
            {
tvData.Nodes[0].Nodes.Add(datSet.Tables[MyTable].Rows[i].ItemArray[2].ToString());
                tvData.Nodes[0].Nodes[i].Tag = "Name";
                tvData.Nodes[0].Nodes[i].ImageIndex = 2;
                tvData.Nodes[0].Nodes[i].SelectedImageIndex = 2;
            }
        }

private void SetCustPhone()
// set Phone field as node
        {
            for (int i = 0; i < itmNumber; i++)
            {
tvData.Nodes[0].Nodes[i].Nodes.Add(datSet.Tables[MyTable].Rows[i].ItemArray[9].ToString());
                tvData.Nodes[0].Nodes[i].Nodes[0].Tag = "Phone";
                tvData.Nodes[0].Nodes[i].Nodes[0].ImageIndex = 4;
                tvData.Nodes[0].Nodes[i].Nodes[0].SelectedImageIndex = 4;
            }
        }

private void DisplayRecord(string EmployeeName)
// Show some data about customer:
        {
            try
            {
                // using DataView to find record:
                DataView dv = new DataView(datSet.Tables[MyTable]);
                dv.Sort = "ContactName";
                int i = dv.Find(EmployeeName);
                this.BindingContext[datSet, MyTable].Position = i;
                txtCompany.Text = datSet.Tables[MyTable].Rows[i].ItemArray[1].ToString();
                txtAddress.Text = datSet.Tables[MyTable].Rows[i].ItemArray[4].ToString();
                txtCity.Text = datSet.Tables[MyTable].Rows[i].ItemArray[5].ToString();
                txtCountry.Text = datSet.Tables[MyTable].Rows[i].ItemArray[8].ToString();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
            }
        }

Summary

I hope that this article be useful in case of use TreeView control, so I invite you to go to source file to read the code about TreeView events. If you have any idea about this code, please tell me. Thanks for C# Corner team and thanks for all.