private void txtMaSinhVien_EditValueChanged(object sender, EventArgs e) { DataTable dtTemp = oBSV_SinhVien.KiemTraMaSV(txtMaSinhVien.Text.Trim()); if (dtTemp != null && dtTemp.Rows.Count > 0 && txtMaSinhVien.Text.Trim() != "" && Sua == false) { SV_SinhVienID = int.Parse(dtTemp.Rows[0]["SV_SinhVienID"].ToString()); txtSoPhieu.Text = GetSoPhieu(Program.HocKy, Program.IDNamHoc, SV_SinhVienID, IDDM_DiaDiem); LoadThongTin(); } else if (txtMaSinhVien.Text.Trim() != "") { txtTenLop.Text = ""; txtHoVaTen.Text = ""; SV_SinhVienID = 0; grdLoaiThuChi.DataSource = null; } }