Lambda expression cannot be converted to '<typename>' because '<typename>' is not a delegate type

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Lambda expressions can be used where delegates are valid. They can be converted to compatible delegate types, but not to any other type. For example, you can define a delegate type and assign a lambda expression to it, or send a lambda expression as the argument to a Func<TResult> parameter. These examples are shown in the following code.

Module Module1

    Delegate Function FunDel(ByVal m As Integer) As Boolean

    Sub Main()

        ' Assign a lambda expression to a function delegate.
        Dim negative As FunDel = Function(n As Integer) n < 0
        Console.WriteLine(negative(-3))

        ' Send a lambda as the argument to a delegate parameter.
        Dim numbers() As Integer = {3, 4, 2, 8, 1, 0, 9, 13, 42}
        Dim evens = numbers.Where(Function(n) n Mod 2 = 0)

        For Each even In evens
            Console.WriteLine(even)
        Next

    End Sub

End Module

Error ID: BC36625

See Also

Concepts

Lambda Expressions