Compiling and executing code using anonymous types with VBCodeProvider fails RRS feed

  • Question

  • Using VBCodeProvider I am trying to compile and execute a block of VB code that performs a LINQ query and then processes the results. Two problems:

    1. The code will not compile unless the anonymous types are declared as Object 

    2. After declaring as Object the methods are not found.

    I have searched high and low for a solution but found nothing of any use.

    Code to Compile (embedded in project as string resource)

        Imports System.Linq
        Imports System.Collections.Generic
        Imports System

        public Class Y

        Friend Shared Function Result() as Integer

        Dim gts As List(Of GtDef) = {New GtDef(1, "FirstGte"), New GtDef(2, "FirstGte")}.Cast(Of GtDef).ToList

        Dim evts As List(Of EvDef) = {New EvDef(1, 1, "FirstEv"), New EvDef(2, 1, "SecondEv"), New EvDef(3, 2, "SecondEv")}.Cast(Of EvDef).ToList

        Dim x = From g In gts Join e In evts On g.ID Equals e.ParentID Group e By key = e.ParentID Into Group Select GtGroup = key, EvGroup = Group

        Dim sum As Integer = x.Count()

        For Each gte In x
          For Each evt In gte.EvGroup
            sum += evt.ID

        return sum

        End Function

        End Class

        Public Class GtDef

        Public ID As Integer
        Public Name As String

        Sub New(id As Integer, name As String)

            Me.ID = id
            Me.Name = name

        End Sub

        End Class

        Public Class EvDef

        Public ID As Integer
        Public ParentID As Integer
        Public Name As String

        Sub New(id As Integer, parentID As Integer, name As String)

             Me.ID = id
             Me.ParentID = parentID
             Me.Name = name

          End Sub

        End Class

    Code used run compiler

        Dim compiler As Compiler.CodeDomProvider = Nothing

        Dim provOptions As New Dictionary(Of String, String)
        provOptions.Add("CompilerVersion", "v4.0")

        compiler = New Microsoft.VisualBasic.VBCodeProvider(provOptions)

        Dim compilerParams As New Compiler.CompilerParameters()

        Dim assems As String() = AppDomain.CurrentDomain.GetAssemblies().Where(Function(find) Not find.IsDynamic).Select(Function(find) find.Location).ToArray

        Dim compResults As Compiler.CompilerResults = compiler.CompileAssemblyFromSource(compilerParams, {My.Resources.Code})

        Dim cls As Type = compResults.CompiledAssembly.GetType("Y")
        cls.InvokeMember("Result", System.Reflection.BindingFlags.InvokeMethod Or System.Reflection.BindingFlags.NonPublic Or System.Reflection.BindingFlags.Static, Nothing, Nothing, Nothing)

    Friday, January 31, 2014 9:49 AM


  • Try adding these lines at the beginning of your resource string:

    Option Explicit On
    Option Infer On

    If you still receive compilation errors in compResults.Errors, then show them.

    Saturday, February 1, 2014 5:22 PM