protected void gvMedicine_Sorting(object sender, GridViewSortEventArgs e) { BindGridDataMedicine(); DataTable dt = LINQToDataTable(dc.GetMedicine()); // dt = ds.Tables[0]; string SortDir = string.Empty; if (dir == SortDirection.Ascending) { dir = SortDirection.Descending; SortDir = "Desc"; } else { dir = SortDirection.Ascending; SortDir = "Asc"; } DataView sortedView = new DataView(dt); sortedView.Sort = e.SortExpression + " " + SortDir; gvMedicine.DataSource = sortedView; gvMedicine.DataBind(); }