private void BtnThemDocGia_Click(object sender, EventArgs e) { if (checkNullForm() == false) { if (txtTienNo.Text.Trim().Equals("")) { txtTienNo.Text = "0"; } if (checkDateTime() == false) { DocGia dg = new DocGia(); dg.ThemDocGia(txtNameDG.Text, datePickerNSDG.Value, txtAddressDG.Text, txtEmailDG.Text, datePickerNgayLapThe.Value, datePickerNgayHetHan.Value, Int16.Parse(txtTienNo.Text)); loadDocGia(); } } }