public int SoLuongNhap()
{
int x;
string sql = "select SoLuong From Hang2 where MaHH = '" + QL_HoaDon.fmHD.cboMaHH.Text + "'";
x = data.ExecuteScalar(sql);
return(x);
}
public int DoanhThuNgay(String theoNgay)
{
int x;
DateTime ngay = Convert.ToDateTime(theoNgay);
string sql = "select sum(SoLuongBan*DonGiaBan) from DoanhThu2 where NgayLap = '" + ngay + "' group by NgayLap";
x = data.ExecuteScalar(sql);
return(x);
}