Question

I have two classes, one nested in the other.

Public Class Operation

    Public Property Name
    Public Property Records As List(Of Record)

    Public Class Record

        Public Property ID as Integer

Now, I have a collection of operations –>

Dim pOperations as List(Of Operation)

Neither “Name” or “ID” are unique between operations and records.

I wish to construct a dictionary using LINQ = Dictionary(Of String, Of List(Of Integer), whereby the keys are uniqe examples of Names in my collection and the values are the collective set of distinct IDs that are associated with those names.

Answer 1

Tim Scmelter’s suggested code pretty much did the trick. I had to make one small change to make my record IDs unique and it was good-to-go.

Dim dict = (From op In pOperations _
            From rec In op.Records _
            Group rec By op.Name Into NameGrp = Group) _
           .ToDictionary(Function(grp) (grp.Name), _
                         Function(grp) (grp.NameGrp.Select(Function(r) _ 
                                                           (r.ID)).Distinct().ToList))