Question

I have this, one datatable and one entity class that I can convert to a datatable.

UC010_WizardStepBusinessParkDataSet dataSet = new UC010_WizardStepBusinessParkDataSet();
        View_BuildingModule_UC010_BusinessPark_Wizard_GetBusinessParkData vwBusPark = new View_BuildingModule_UC010_BusinessPark_Wizard_GetBusinessParkData();

I want to return with a LINQ query the ones that are in vwBusPark that are not in dataset.BusinessPark.

I was trying something like the following but I am stuck:

   var query = dataSet.BusinessPark.Where(entry => !vwBusPark.toDataTable().AsEnumerable().Contains(entry.BusinessParkID));

It says:

Error 1 The type arguments for method ‘System.Linq.Enumerable.Contains(System.Collections.Generic.IEnumerable, TSource)’ cannot be inferred from the usage. Try specifying the type arguments explicitly. C:\BITProjects\TeamSystem\luival\refm\DEV\BuildingModule\Business\UC010_BusinessPark_Wizard\BusinessParkWizardBL.cs 42 62 Ceusters.REFM.BuildingModule.Business

Answer 1

Try

var vwBusParkIDs = vwBusPark.toDataTable().AsEnumerable().Select(r => Convert.ToInt32( r["BusinessParkId"]));
var query = dataSet.BusinessPark.Where(entry => !vwBusParkIDs.Contains(entry.BusinessParkID));