how to delete a row in gridview

Question

//int id = Convert.ToInt32(GridView1.DataKeys[e.RowIndex].Values[0].ToString());

//if (con.State == ConnectionState.Closed)

//{

// con.Open();

//}

//SqlCommand cmd = new SqlCommand("Delete from gridview where id='" + id + "'", con);

//cmd.ExecuteNonQuery();

//con.Close();

//GridView1.DataBind();

//display();

 how can i delete a row in using row deleting event . i was used this code but its not working in the table i use identity to generate id