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LINQ - SELECT certain columns


If your result no longer contains an Address, it's no longer a Person.

The following does work:

Dim test = From p In list
           Where p.Name = "Ian"
           Select New With { .Name = p.Name, .Age
= p.Age }

This creates a new, anonymous type which only contains the information you are interested in. The type of test is IEnumerable(Of SomeAnonymousTypeThatDoesNotHaveAName).


In general, the purpose of the Select clause is to do a projection. For example, you could project your persons to strings:

Dim namesWithAges As IEnumerable(Of
String) = 
    From p In list Select p.Name & " (" &
p.Age & ")"

or to some completely new object:

Dim employees = 
    From p In list
    Select New With { .Name = p.Name, .Supervisor
= DetermineSupervisor(p) }

Categories : Vb.Net

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