Question

I’ve got the following ADO.NET Entity Framework Entity Data Model:

I want to find all the Policyholders with both a Service of a given Id and also a Keyword of a given Status.

This LINQ Does Not Work:

Dim ServicesId As Integer = ... Dim KeywordStatus As Integer = ...  Dim FoundPolicyholders = From p As Policyholder In db.PolicyholderSet.Include('Keywords').Include('Services') _                          Where p.Services.Id = ServicesId _                          And p.Keywords.Status = KeywordStatus _                          Select p 

The Where clause cannot search the p.Services and p.Keywords EntityCollections in that way.

‘Id’ is not a member of ‘System.Data.Objects.DataClasses.EntityCollection(Of ….Service)’.

What is the correct LINQ syntax to do what I want?

Answer 1

db.PolicyholderSet.Where(ph =>    ph.Services.Any(s => s.Id == someId) &&    ph.Keywords.Any(kw => kw.Status == someStatus)) 

Why does your query not work? Because p.Services and p.Keywords are a Service and a Keyword collection – they have not property Id or Status hence you cannot use p.Services.Id or p.Keywords.Status.

Visual Basic…

Dim FoundPolicyholders = From p As Policyholder In db.PolicyholderSet.Include('Keywords').Include('Services') _                          Where p.Services.Any(Function(s) s.Id = ServicesId) _                          And p.Keywords.Any(Function(k) k.Status = KeywordStatus) _                          Select p