private void LoadDanhSachLoaiDienThoai()
{
clsLoaiDT_BUS _loaiBUS = new clsLoaiDT_BUS();
cboLoaiDT.DataSource = _loaiBUS.DanhSachLoaiDT();
cboLoaiDT.DisplayMember = "TenLoaiDT";
cboLoaiDT.ValueMember = "MaLoaiDT";
}
