private void btnLoadDeTai_Click(object sender, EventArgs e) { var dtpc = from x in dbs.PhanCongs select new { x.TenDeTai, x.NamHoc, x.HocKy }; var detai = dbs.sp_getDeTaiChuaDuocPhanCong(Convert.ToInt32(cbbHocKy.Text), Convert.ToInt32(cbbNamHoc.Text)); cbbTenDT.DataSource = detai.ToList(); cbbTenDT.DisplayMember = "TenDT"; }