private void GetBooksBought() { ELibraryDocumentBL docBL = new ELibraryDocumentBL(); UserDetails userObj = (UserDetails)Session["UserObj"]; List <int> docIDList = docBL.GetDocumentsBoughtBL(userObj.UserID); gvPurchased.DataSource = null; if (docIDList != null) { DataTable dt = new DataTable(); dt.Columns.Add(new DataColumn("Title", typeof(string))); dt.Columns.Add(new DataColumn("Author", typeof(string))); dt.Columns.Add(new DataColumn("Description", typeof(string))); dt.Columns.Add(new DataColumn("Price", typeof(string))); foreach (int docId in docIDList) { DocumentDetails doc = docBL.GetDocumentByID(docId); DataRow dr = dt.NewRow(); dr["Title"] = doc.Title; dr["Author"] = doc.Author; dr["Description"] = doc.DocumentDescription; dr["Price"] = doc.Price; dt.Rows.Add(dr); } gvPurchased.DataSource = dt; gvPurchased.DataBind(); } }