Public Function CreateAssemblyFromCode(ByVal Code As String) As [Assembly]
        Dim CDP As CodeDomProvider = New Microsoft.VisualBasic.VBCodeProvider        
        Dim Compiler As ICodeCompiler = CDP.CreateCompiler()
        Dim CP As New CompilerParameters(New String() {"System.Data.Dll"})
        CP.GenerateInMemory = True
        Dim CR As CompilerResults = Compiler.CompileAssemblyFromSource(CP, Code)
        If CR.Errors.Count <> 0 Then
            For Each ce As System.CodeDom.Compiler.CompilerError In CR.Errors
                Debug.WriteLine(ce.ErrorText)
            Next
            Return Nothing
        Else
            Return CR.CompiledAssembly
        End If
    End Function
 
    Private obj As Object
    Private method As MethodInfo
 
    Private Sub CompileMethod(ByVal str As String)
        Dim Code As String = _
            "Imports System.Data.OleDb " & vbCrLf & _
            "Namespace test " & vbCrLf & _
              "Public Class GetData " & vbCrLf & _
                "Public Function GetData(ByVal dr As OleDbDataReader) As String" & _
                "" & vbCrLf & _
                  "Return " & str & vbCrLf & _
                "End Function " & vbCrLf & _
              "End Class " & vbCrLf & _
            "End Namespace"
        'Debug.WriteLine(Code)
 
        Dim asm As [Assembly] = CreateAssemblyFromCode(Code)
        obj = asm.CreateInstance("test.GetData")
        method = obj.GetType().GetMethod("GetData")
    End Sub
 
    Public Sub trx()
        Dim str As String = "dr(""ShipName"").SubString(0,7)"
        Dim sql1 As String = "SELECT * from Orders"
        Dim conn As New OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0; Data" & _
          "Source=nwind.mdb;")
        Dim cmd As New OleDbCommand(sql1, conn)
        Try
            CompileMethod(str)
            cmd.Connection.Open()
            Dim dbDR As OleDb.OleDbDataReader = cmd.ExecuteReader()
            While dbDR.Read()
                Dim val As String = CType(method.Invoke(obj, New Object() _
                  {dbDR}), String)
                MsgBox(val)
            End While
        Catch ex As Exception
            MsgBox(ex.ToString())
        Finally
            cmd.Connection.Close()
        End Try
    End Sub