Imports System

Imports System.Collections.Generic

Imports System.Linq

Imports System.IO

​

Public Module Module1

    Public Sub Main()

        Dim test As String =

"12313 banana milkshake

12356 choco milkshake

kiwi milkshake 1231313"

        Dim lines = GetLines(test).

            Where(Function(line) line.Contains("kiwi") OrElse line.Contains("choco"))

​

        For Each line As String In lines

            Console.WriteLine(line)

        Next        

    End Sub

    Public Iterator Function GetLines(input As String) As IEnumerable(Of String)

        Dim line As String = Nothing

        Using rdr As New StringReader(input) ' Not StreamReader!

            line = rdr.ReadLine()

            While line IsNot Nothing

                Yield line

                line = rdr.ReadLine()

            End While

        End Using

    End Function

End Module