How to AutoComplete TextBox or ComboBox in Winforms

namespace AutoCompleteTextBox
{
public partial class frmAuto : Form
{
public string strConnection = ConfigurationManager.AppSettings["ConnString"];
AutoCompleteStringCollection namesCollection = new AutoCompleteStringCollection();
public frmAuto()
{
InitializeComponent();
}
private void frmAuto_Load(object sender, EventArgs e)
{
SqlDataReader dReader;
SqlConnection conn = new SqlConnection();
conn.ConnectionString = strConnection;
SqlCommand cmd = new SqlCommand();
cmd.Connection = conn;
cmd.CommandType = CommandType.Text;
cmd.CommandText = "Select distinct [Name] from [Names] order by [Name] asc";
conn.Open();
dReader = cmd.ExecuteReader();
if (dReader.HasRows == true)
{
while (dReader.Read())
namesCollection.Add(dReader["Name"].ToString());
}
else
{
MessageBox.Show("Data not found");
}
dReader.Close();
txtName.AutoCompleteMode = AutoCompleteMode.Suggest;
txtName.AutoCompleteSource = AutoCompleteSource.CustomSource;
txtName.AutoCompleteCustomSource = namesCollection;
}
private void btnCancel_Click(object sender, EventArgs e)
{
Application.Exit();
}
private void btnOk_Click(object sender, EventArgs e)
{
MessageBox.Show("Hope you like this example");
}
}
}