private void frmPhieuMuonSach_Load(object sender, EventArgs e)
{
cbHoTen.DataSource = bus.LayThongtinHT("where iddocgia ='" + _message + "'");
cbHoTen.ValueMember = "hoten";
BUS_Sach buss = new BUS_Sach();
DataTable dt = buss.LayDanhSachSach();
string showid = "select iddocgia from DocGia where hoten = '" + cbHoTen.Text + "'";
db.LoadData2Label(lbid, showid);
//cbmasach.DisplayMember = "masach";
//cbtacgia.DisplayMember = "tacgia";
//cbtensach.DisplayMember = "tensach";
//cbtheloai.DisplayMember = "theloai";
cbmasach.ValueMember = "masach";
cbtacgia.ValueMember = "tacgia";
cbtensach.ValueMember = "tensach";
cbtheloai.ValueMember = "theloai";
cbmasach.DataSource = dt;
cbtacgia.DataSource = dt;
cbtheloai.DataSource = dt;
cbtensach.DataSource = dt;
}