DataGridについて教えて下さい。

private void button1_Click(object sender, System.EventArgs e)
{
	SqlDataAdapter da = new SqlDataAdapter(
		"SELECT EmployeeID, FirstName, LastName FROM Employees",
		"server=.;database=Northwind;uid=sa;pwd=sa");
	DataSet ds = new DataSet();
	da.Fill(ds, "Employees");
	dataGrid1.DataSource = ds;
	dataGrid1.DataMember = "Employees";

	DataGridTableStyle dgts = new DataGridTableStyle();
	dgts.MappingName = "Employees";

	DataGridColumnStyle TextCol0 = new DataGridTextBoxColumn();
	TextCol0.MappingName = "EmployeeID";
	TextCol0.HeaderText = "Employee Identification";
	TextCol0.Width = 250;
	dgts.GridColumnStyles.Add(TextCol0);

	DataGridColumnStyle TextCol1 = new DataGridTextBoxColumn();
	TextCol1.MappingName = "FirstName";
	TextCol1.HeaderText = "First Name";
	TextCol1.Width = 250;
	dgts.GridColumnStyles.Add(TextCol1);

	DataGridColumnStyle TextCol2 = new DataGridTextBoxColumn();
	TextCol2.MappingName = "LastName";
	TextCol2.HeaderText = "Last Name";
	TextCol2.Width = 250;
	dgts.GridColumnStyles.Add(TextCol2);

	dataGrid1.TableStyles.Add(dgts);
}