Question

I have anywhere from 5 to 10 generic list in an ASP.NET VB.NET web app. I would like to write a method to pass them all into, and return only the elements they all have in common.

I’m looking for some ideas how to accomplish this the easiest and cleanest way possible.

Answer 1

To find matching items in a list, try this out:

Module Module1

    Sub Main()

        Dim l1 As New List(Of Integer)
        Dim l2 As New List(Of Integer)

        l1.Add(2)
        l1.Add(5)

        l2.Add(9)
        l2.Add(2)

        Dim k = l1.Intersect(l2).ToList ' Will have one item, the number 2.
    End Sub

End Module

Use the Intersect extension method to help you.