private void btnsearch_Click(object sender, EventArgs e)
        {
            string   prenum, iran, lastnum, letter, a, name;
            frmfindd f22 = new frmfindd(this);

            if (combosearchby.Text == "پلاک")
            {
                prenum  = txtyear.Text;
                letter  = txtmonth.Text;
                lastnum = txtday.Text;
                iran    = txtiran.Text;
                a       = "select * From Tblaccounting where prenum='" + prenum + "' and letter=N'" + letter + "' and lastnum='" + lastnum + "'and Iran='" + iran + "'";
                fillgrid(a);
            }
        }
        private void bunifuThinButton21_Click(object sender, EventArgs e)
        {
            frmfindd f22 = new frmfindd(this);

            f22.ShowDialog();
        }