Question

http://msdn.microsoft.com/en-us/library/bb763133.aspx

Module Module1
    Sub Main()
        Dim array1 As Func(Of Integer)() = New Func(Of Integer)(4) {}

        For i As Integer = 0 To 4
            array1(i) = Function() i
        Next

        For Each funcElement In array1
            System.Console.WriteLine(funcElement())
        Next

    End Sub
End Module

It says the result will always be 5 namely the final value of i. How come?

They don’t put the iteration variable in the “closure”?

Answer 1

The problem occurs because lambda expressions do not execute when they are constructed but rather when they are invoked.

See the link below:
http://blogs.msdn.com/b/vbteam/archive/2007/07/26/closures-in-vb-part-5-looping.aspx

Hope it helps.