private void FrmSach_Load(object sender, EventArgs e)
{
string show = "select DISTINCT theloai from Sach where theloai is not null";
db.LoadData2Combobox(cbtls, show);
KhoaDieuKien();
HienThi("");
lbllimittime.Text = "Thời hạn của sách: " + Time + " năm";
}
private void FrmBaoCaoI_Load(object sender, EventArgs e)
{
string loadthang = "select distinct thang from BaoCaoI";
db.LoadData2Combobox(cbThang, loadthang);
bus.truyendl();
}