How to add a new row in a combobox?

Question

I developed a Pocket PC app. It works but i wanna add a new (without data) row in a combobox:

      SqlCeCommand sql3 = new SqlCeCommand("SELECT (ACM_EMPL.NUM_EMPL + '~' + ACM_EMPL.NOM_EMPL) AS NUM_EMPL FROM ACM_EMPL INNER JOIN ACM_ACT ON ACM_EMPL.NUM_EMPL = ACM_ACT.NUM_EMPL WHERE (ACM_ACT.NUM_ACTIVO = '" + oc.Text + "'AND ACM_ACT.NUM_CIA = '" + CIA.Text + "' AND ACM_ACT.NUM_TIPO = '" + TIPO.Text + "' AND ACM_ACT.SUB_NUM_ACT = '" + SUBNUM.Text + "') ", conn);
        sql3.ExecuteNonQuery();
        SqlCeDataAdapter cb3 = new SqlCeDataAdapter(sql3);
        DataTable dt3 = new DataTable();
        cb3.Fill(dt3);
        foreach (DataRow dr3 in dt3.Rows)
        {
            ma.cmbEmpleado.SelectedValue = dr3["NUM_EMPL"].ToString();
        }

It shows:

I wanna add a "-select-" or a " " Row, how could i do it? i tryed with

    dt3.Rows.Add("----------");

and things like these, but it doesnt work!.

Thank you

Answer 1

try this:

            SqlCeCommand sql3 = new SqlCeCommand("SELECT (ACM_EMPL.NUM_EMPL + '~' + ACM_EMPL.NOM_EMPL) AS NUM_EMPL FROM ACM_EMPL INNER JOIN ACM_ACT ON ACM_EMPL.NUM_EMPL = ACM_ACT.NUM_EMPL WHERE (ACM_ACT.NUM_ACTIVO = '" + oc.Text + "'AND ACM_ACT.NUM_CIA = '" + CIA.Text + "' AND ACM_ACT.NUM_TIPO = '" + TIPO.Text + "' AND ACM_ACT.SUB_NUM_ACT = '" + SUBNUM.Text + "') ", conn);
        sql3.ExecuteNonQuery();
        SqlCeDataAdapter cb3 = new SqlCeDataAdapter(sql3);
        DataTable dt3 = new DataTable();
        cb3.Fill(dt3);
        if (dt3.Rows.Count > 0)
        {

            ma.cmbEmpleado.DataSource = dt;
            ma.cmbEmpleado.DataValueField = dt3.Columns["NUM_EMPL"].ToString();
            ma.cmbEmpleado.DataTextField = dt3.Columns["NUM_EMPL"].ToString();
        }
        ma.cmbEmpleado.Items.Insert(0, "---------");
        ma.cmbEmpleado.Items[0].Value = "0";