Linq ResultSet to DataTable

Question

I have a SQL Database which I imported as a ADO.NET Entity Data Model. I then populate a DataGridView using Linq. I extended two of the tables with extra columns that are calculated from other tables. For instance, I have a table Orders that has fields OrderNumber, DateApproved and RequestorID and so on. I also have a table that is the OrderDetails with Fields like SKU, OrderNUmber and QuanityOrdered. I coded a new column IsBackOrdered for the Orders Table that calculates if any Item(SKU) from the OrderDetails is backordered.

When I bound the table Orders to the DataGridView.DataSource everything works as expected. I was then directed to create a search filter for the table.

I tried to map BindingSource to the Linq query but BindingSource is expecting a DataTable. I found a neat little method that converts Linq ResultSet to a DataTable (Code below) however it barfs on my custom fields (Columns) at this line: dr[pi.Name] = pi.GetValue(rec, null) ?? DBNull.Value;

Thanks in advance for any of your view or helpful insights you would care to offer.

public static DataTable LinqToDataTable<T>(IEnumerable<T> varlist)
        {
            var dtReturn = new DataTable();

            // column names
            PropertyInfo[] oProps = null;

            if (varlist == null)
                return dtReturn;

            foreach (T rec in varlist)
            {
                // Use reflection to get property names, to create table, Only first time, others will follow
                if (oProps == null)
                {
                    oProps = rec.GetType().GetProperties();
                    foreach (PropertyInfo pi in oProps)
                    {
                        Type colType = pi.PropertyType;

                        if ((colType.IsGenericType) && (colType.GetGenericTypeDefinition() == typeof(Nullable<>)))
                        {
                            colType = colType.GetGenericArguments()[0];
                        }

                        dtReturn.Columns.Add(new DataColumn(pi.Name, colType));
                    }
                }

                DataRow dr = dtReturn.NewRow();

                foreach (PropertyInfo pi in oProps)
                {
                    dr[pi.Name] = pi.GetValue(rec, null) ?? DBNull.Value;
                }

                dtReturn.Rows.Add(dr);
            }
            return dtReturn;
        }

Answer 1

DataSource property of the BindingSource doesn't expect DataTable. It's of type object, so you may use any list as data source. But in this case to be able to filter it you should either implement IBindingListView or use BindingList. The second case is easier of course. Take a look here for more information.