Question

I got this code

But I got the following errors:

Error   1   Instance argument: cannot convert from 'System.Collections.Generic.IEnumerable<AnonymousType#1>' to 'System.Collections.Generic.IEnumerable<System.Data.DataRow>'   

Error   2   'System.Collections.Generic.IEnumerable<AnonymousType#1>' does not contain a definition for 'CopyToDataTable' and the best extension method overload 'System.Data.DataTableExtensions.CopyToDataTable<T>(System.Collections.Generic.IEnumerable<T>)' has some invalid arguments 



 var distinctRows = (from DataRow dRow in vwBusPark.toDataTable().Rows
                                    select new { col1 = dRow["BusinessParkID"], col2 = dRow["BusinessParkID"] }).Distinct();

                dataSet.BusinessPark.Merge(distinctRows.CopyToDataTable<DataRow>(), true, System.Data.MissingSchemaAction.Ignore);

I tried this:

dataSet.BusinessPark.Merge(vwBusPark.toDataTable().Rows.Except(DataRowComparer<UC010_WizardStepBusinessParkDataSet.BusinessParkRow>.Default).CopyToDataTable(), true, System.Data.MissingSchemaAction.Ignore);

But I got this 2 errors:

Error   2   'System.Collections.Generic.IEnumerable<AnonymousType#1>' does not contain a definition for 'CopyToDataTable' and the best extension method overload 'System.Data.DataTableExtensions.CopyToDataTable<T>(System.Collections.Generic.IEnumerable<T>)' has some invalid arguments 

Error   1   Instance argument: cannot convert from 'System.Collections.Generic.IEnumerable<AnonymousType#1>' to 'System.Collections.Generic.IEnumerable<System.Data.DataRow>'

Answer 1

Those aren’t DataRows, so you can’t copy them to a DataTable.

Assuming that BusinessPark has the same column names as vwBusPark, you don’t need the LINQ query at all; instead, you can just write

vwBusPark.toDataTable().Rows.Except(...).CopyToDataTable()