Did you try the syntax in the code I posted?
( where pdfform is fully qualified path and name to the pdfform )

Dim PdfReader As PdfReader = New PdfReader(pdfform)

Dim fieldlist As New ArrayList(PdfReader.AcroFields.Fields.Keys)


>>Yes that is very much like the situation I had and this worked very well.
>
>I tried that earlier on and was unable to make it work. It seems to be related to the same problem I have in this example:
>
>

>    ' Get all the fields from a PDF file
>    ' expC1 File
>    Private Function GetFields(ByVal tcFile As String) As Boolean
>        Dim loAcroFields As iTextSharp.text.pdf.AcroFields = Nothing
>        Dim loDictionaryEntry As DictionaryEntry = Nothing
>        Dim loPdfReader As iTextSharp.text.pdf.PdfReader = Nothing
>
>        ' Get the file
>        loPdfReader = New iTextSharp.text.pdf.PdfReader(tcFile)
>
>        ' Get the fields
>        loAcroFields = loPdfReader.AcroFields
>
>        ' For each field
>        For Each loDictionaryEntry In loAcroFields.Fields
>
>        Next
>
>        Return True
>    End Function
>

>
>As you can see, this example is very sample. But, the designer doesn't like the loAcroFields.Fields in the For/Next loop. It says:
>
>"Value of type 'System.Collections.Generic.KeyValuePair(Of String, iTextSharp.text.pdf.AcroFields.Item)' cannot be converted to 'System.Collections.DictionaryEntry'."
>
>I also tried with all the imports. This has no effect. In my code, I include the namespace as is where needed.
>
>This is an example I took from http://blog.pagesd.info/post/2008/09/25/Lister-les-champs-d-un-formulaire-PDF.