private void delete_Click(object sender, EventArgs e)
        {
            DialogResult c = MessageBox.Show("Voulez-vous vraiment supprimer le message ", "Comfirmer suppression", MessageBoxButtons.YesNo, MessageBoxIcon.Error);

            if (c == DialogResult.Yes)
            {
                msg l = a.dtc.msg.ToList().SingleOrDefault(f => f.idm == i);
                if (l.adrexp == a.t)
                {
                    if (l.supdes == true)
                    {
                        a.dtc.msg.DeleteOnSubmit(l);
                        a.dtc.SubmitChanges();
                    }
                    else
                    {
                        l.supex = true;
                        a.dtc.SubmitChanges();
                    }
                }
                else
                {
                    if (l.supex == true)
                    {
                        a.dtc.msg.DeleteOnSubmit(l);
                        a.dtc.SubmitChanges();
                    }
                    else
                    {
                        l.supdes = true;
                        a.dtc.SubmitChanges();
                    }
                }
                if (btn == 0)
                {
                    a.bre_Click(null, null);
                }
                else
                if (btn == 2)
                {
                    a.ben_Click(null, null);
                }
                else
                {
                    a.mfav_Click(null, null);
                }
            }
        }