Refreshing my database

See where I put that line of code. But its doesnt. I dont know what happen?

conn = new SqlConnection(connstr);

comm = new SqlCommand();

conn.Open();

SqlParameter firstname = new SqlParameter("@firstname", SqlDbType.VarChar);

SqlParameter lastname = new SqlParameter("@lastname", SqlDbType.VarChar);

comm.Parameters.Add(firstname);

comm.Parameters.Add(lastname);

firstname.Value = txtfirstname.Text;

lastname.Value = txtlastname.Text;

comm.Connection = conn;

comm.CommandText = "insert into test values(@firstname,@lastname)";

try

{

comm.ExecuteNonQuery();

MessageBox.Show("Saved!");

}

catch (Exception)

{

MessageBox.Show("Not saved");

}

finally

{

conn.Close();

}

}

}

Not to clear. It's just like close/open to have data always refreshed. Means the last record should appear in my datagridview instantly after saving.

I fill it like this in load event

string connectionString = @"Data Source=localhost\sqlexpress;Initial Catalog=master;Integrated Security=True";

            string sql = "SELECT * FROM test";

            SqlConnection connection = new SqlConnection(connectionString);

            SqlDataAdapter dataadapter = new SqlDataAdapter(sql, connection);

            DataSet ds = new DataSet();

            connection.Open();

            dataadapter.Fill(ds, "test");

            connection.Close();

            dgv.DataSource = ds;

            dgv.DataMember = "test";

            dgv.CurrentCell = dgv.Rows[dgv.Rows.Count - 1].Cells[0];