public int Delete(int id)
{
// Kiem tra xem lop do co sv nao khong
List <Lop> ds = Select("id=" + id);
if (ds.Count > 0)
{
Lop l = ds[0];
if (l.DanhSach().Count > 0)
{
// Khong the xoa
return(-2);
}
}
String query = "Delete tbLop Where id=" + id.ToString();
int dem = da.Write(query);
return(dem);
}
public List <Lop> Select(String condition)
{
String query = "Select * from tbLop Where " + condition;
DataTable tb = da.Read(query);
if (tb != null && tb.Rows.Count > 0)
{
List <Lop> ds = new List <Lop>();
foreach (DataRow r in tb.Rows)
{
Lop sv = new Lop();
sv.ID = int.Parse(r["ID"].ToString());
sv.Ten = r["Ten"].ToString();
ds.Add(sv);
}
return(ds);
}
else
{
return(null);
}
}