parameterise grid display

   SqlConnection con = new SqlConnection("Data Source=ANKITA-USER18\\SQL2008R2;Integrated Security=True;Initial Catalog=hrdemo");

        SqlDataAdapter da = new SqlDataAdapter();
        da.SelectCommand = new SqlCommand();
        //SqlCommandBuilder c = new SqlCommandBuilder(da);
        da.SelectCommand.CommandText = "select * from emp where id=@p1";
        da.SelectCommand.Connection = con;
        da.SelectCommand.Parameters.Add("@p1", SqlDbType.Int);
        da.SelectCommand.Parameters[0].Value = 1;
        DataSet ds = new DataSet();
        da.Fill(ds);
        GridView1.DataSource = ds;
        GridView1.DataBind();