''' <summary>
''' Removes an interactive field from interactive form of PDF document.
''' </summary>
''' <param name="pdfFilename">The filename of PDF document.</param>
''' <param name="fullyQualifiedFieldName">The name of field.</param>
Public Shared Sub RemoveFieldFromPdfInteractiveForm(pdfFilename As String, fullyQualifiedFieldName As String)
    ' open PDF document
    Using document As New Vintasoft.Imaging.Pdf.PdfDocument(pdfFilename)
        ' if PDF document has interactive form
        If document.InteractiveForm IsNot Nothing Then
            ' get reference to the interactive form
            Dim form As Vintasoft.Imaging.Pdf.Tree.InteractiveForms.PdfDocumentInteractiveForm = document.InteractiveForm

            ' remove field from interactive form
            form.RemoveField(fullyQualifiedFieldName)

            ' save changes to a file
            document.SaveChanges()
        End If
    End Using
End Sub

/// <summary>
/// Removes an interactive field from interactive form of PDF document.
/// </summary>
/// <param name="pdfFilename">The filename of PDF document.</param>
/// <param name="fullyQualifiedFieldName">The name of field.</param>
public static void RemoveFieldFromPdfInteractiveForm(string pdfFilename, string fullyQualifiedFieldName)
{
    // open PDF document
    using (Vintasoft.Imaging.Pdf.PdfDocument document =
        new Vintasoft.Imaging.Pdf.PdfDocument(pdfFilename))
    {
        // if PDF document has interactive form
        if (document.InteractiveForm != null)
        {
            // get reference to the interactive form
            Vintasoft.Imaging.Pdf.Tree.InteractiveForms.PdfDocumentInteractiveForm form = document.InteractiveForm;

            // remove field from interactive form
            form.RemoveField(fullyQualifiedFieldName);

            // save changes to a file
            document.SaveChanges();
        }
    }
}