Here is the solution that worked for me... It needs bit of cleaning which will now happen after the long weekend.
Private Sub btnExtractMerge_Click(sender As Object, e As EventArgs) Handles btnExtractMerge.Click
txtCurSetupMessages.Text = ""
ShowMessage(txtCurSetupMessages, "Extract & Merge Process Started")
'get and check the paths / files from the form
Dim baseDir As String = txtCurSetupBaseDataFolder.Text
Dim baseInvDir As String = txtCurSetupInvoicesFolder.Text
Dim baseFileName As String = txtEMBaseFile.Text
Dim targetFileName As String = txtEMTargetFile.Text
If String.IsNullOrWhiteSpace(baseDir) Then
ShowMessage(txtCurSetupMessages, "Base folder empty!")
Exit Sub
End If
If String.IsNullOrWhiteSpace(baseInvDir) Then
ShowMessage(txtCurSetupMessages, "Base invoice folder name empty!")
Exit Sub
End If
If String.IsNullOrWhiteSpace(baseFileName) Then
ShowMessage(txtCurSetupMessages, "Base file name empty!")
Exit Sub
End If
If String.IsNullOrWhiteSpace(targetFileName) Then
ShowMessage(txtCurSetupMessages, "Target file name empty!")
Exit Sub
End If
If Not Directory.Exists(baseDir) Then
ShowMessage(txtCurSetupMessages, "Base folder does not exist!")
Exit Sub
End If
baseInvDir = System.IO.Path.Combine(baseDir, baseInvDir)
If Not Directory.Exists(baseInvDir) Then
ShowMessage(txtCurSetupMessages, "Base invoice folder does not exist!")
Exit Sub
End If
'get the invoice files
Dim dirInfo As DirectoryInfo = New DirectoryInfo(baseInvDir)
Dim files As FileInfo() = dirInfo.GetFiles("*.pdf")
If files.Length <= 0 Then
ShowMessage(txtCurSetupMessages, "Invoices missing!")
Exit Sub
End If
baseFileName = System.IO.Path.Combine(baseDir, baseFileName)
If Not File.Exists(baseFileName) Then
ShowMessage(txtCurSetupMessages, "Base file missing!")
Exit Sub
End If
targetFileName = System.IO.Path.Combine(baseDir, targetFileName)
If File.Exists(targetFileName) Then
File.Delete(targetFileName)
End If
Dim tempSource As String = System.IO.Path.Combine(baseDir, "tempSource.pdf")
If File.Exists(tempSource) Then
File.Delete(tempSource)
End If
'copy the base file as temp file
File.Copy(baseFileName, tempSource, True)
'do action
Dim iteration As Integer = 1
Dim totalPages As Integer = 0
Dim page As Integer = 0
Dim temp As String = System.IO.Path.Combine(baseDir, "temp.pdf")
Dim tempBefore As String = System.IO.Path.Combine(baseDir, "tempBefore.pdf")
Dim tempAfter As String = System.IO.Path.Combine(baseDir, "tempAfter.pdf")
Dim reader As PdfReader = Nothing
For Each myFile As FileInfo In files
If File.Exists(temp) Then File.Delete(temp)
If File.Exists(tempBefore) Then File.Delete(tempBefore)
If File.Exists(tempAfter) Then File.Delete(tempAfter)
'get total pages in the pdf
reader = New PdfReader(tempSource)
totalPages = reader.NumberOfPages
reader.Close()
If totalPages = 0 Then
ShowMessage(txtCurSetupMessages, String.Format("0 pages found in the source file"))
Exit For
End If
'find page number, this is the page after which we'll place the invoice pdf
page = FindPageNo(tempSource, 1, myFile.Name.ToUpper.Replace(".PDF", ""))
If page <= 0 Then Continue For
ShowMessage(txtCurSetupMessages, String.Format("Processing Invoice:{0} Page:{1} InvoiceFile:{2}", Format(iteration, "000"), Format(page + 1, "000"), myFile.Name))
If page = totalPages Then
'append the invoice file to the end
AddDocuments(temp, tempSource, myFile.FullName, "")
Else
'divide the pages into temp before and temp after then put together
BuildTempBeforeAndAfter(tempSource, tempBefore, tempAfter, page, totalPages)
'now put together
AddDocuments(temp, tempBefore, myFile.FullName, tempAfter)
End If
'move the temp into temp source
If File.Exists(temp) Then
File.Copy(temp, tempSource, True)
End If
iteration += 1
Next
'clean reader, used for temp number of pages
If Not reader Is Nothing Then reader.Close()
'clean the temp files used by the loop
If File.Exists(temp) Then File.Delete(temp)
If File.Exists(tempBefore) Then File.Delete(tempBefore)
If File.Exists(tempAfter) Then File.Delete(tempAfter)
'move temp source to target file and delete
If File.Exists(tempSource) Then
File.Copy(tempSource, targetFileName, True)
File.Delete(tempSource)
End If
ShowMessage(txtCurSetupMessages, "Process Completed")
End Sub
Private Function FindPageNo(ByVal sourceFiles As String, ByVal startpage As Integer, ByVal invno As String) As Integer
Dim i As Integer
Dim str1 As String
Dim pos1 As Integer, pos2 As Integer
Dim bgReader As PdfReader
Dim pagen As Integer
If File.Exists(sourceFiles) Then
bgReader = New PdfReader(sourceFiles)
If startpage > bgReader.NumberOfPages Then
FindPageNo = -1 'error. invalid
bgReader.Close()
End If
pagen = 0
For i = startpage To bgReader.NumberOfPages
str1 = pdftextextractor.GetTextFromPage(bgReader, i)
pos1 = str1.IndexOf("Invoice No:")
pos2 = str1.IndexOf("Phone:")
If pos2 > pos1 Then
If str1.Substring(pos1 + 11, pos2 - pos1 - 11).Trim.Equals(invno) = True Then
pagen = i 'found the page
'bgReader.Close()
'Exit Function
Else
If pagen <> 0 Then
'we found the page no. so no need to go further.
'exit now
FindPageNo = pagen 'last page found
bgReader.Close()
Exit Function
End If
End If
End If
Next i
bgReader.Close()
End If
If pagen <> 0 Then
FindPageNo = pagen 'last page found
Else
FindPageNo = 0 'not found
End If
End Function
Private Function BuildTempBeforeAndAfter(ByVal tempSource As String, ByVal tempBefore As String, ByVal tempAfter As String, ByVal endPage As Integer, ByVal totalPages As Integer) As Boolean
Dim reader As PdfReader = Nothing
Dim copy As PdfCopy = Nothing
Dim doc As Document = Nothing
Dim impPage As PdfImportedPage = Nothing
Dim isBuild As Boolean = True
Try
reader = New PdfReader(tempSource)
doc = New Document(reader.GetPageSizeWithRotation(1))
'before file
copy = New PdfCopy(doc, New FileStream(tempBefore, FileMode.Create))
doc.Open()
For index = 1 To endPage
impPage = copy.GetImportedPage(reader, index)
copy.AddPage(impPage)
Next
copy.Close()
doc.Close()
'after file
doc = New Document(reader.GetPageSizeWithRotation(1))
copy = New PdfCopy(doc, New FileStream(tempAfter, FileMode.Create))
doc.Open()
For index = endPage + 1 To totalPages
impPage = copy.GetImportedPage(reader, index)
copy.AddPage(impPage)
Next
reader.Close()
copy.Close()
doc.Close()
Catch ex As Exception
isBuild = False
Finally
'clean the objects
If Not reader Is Nothing Then reader.Close()
If Not doc Is Nothing Then doc.Close()
If Not reader Is Nothing Then reader.Close()
End Try
Return isBuild
End Function
Private Function AddDocuments(ByVal targetFile As String, ByVal addFile1 As String, ByVal addFile2 As String, ByVal addFile3 As String) As Boolean
Dim reader As PdfReader = Nothing
Dim copy As PdfCopy = Nothing
Dim doc As Document = Nothing
Dim isAdded As Boolean = True
Try
doc = New Document
copy = New PdfSmartCopy(doc, New FileStream(targetFile, FileMode.Create))
doc.Open()
'add file 1
If Not String.IsNullOrWhiteSpace(addFile1) Then
reader = New PdfReader(addFile1)
copy.AddDocument(reader)
reader.Close()
End If
'add file 2
If Not String.IsNullOrWhiteSpace(addFile2) Then
reader = New PdfReader(addFile2)
copy.AddDocument(reader)
reader.Close()
End If
'add file 3
If Not String.IsNullOrWhiteSpace(addFile3) Then
reader = New PdfReader(addFile3)
copy.AddDocument(reader)
reader.Close()
End If
copy.Close()
doc.Close()
Catch ex As Exception
isAdded = False
Finally
'clean the objects
If Not reader Is Nothing Then reader.Close()
If Not doc Is Nothing Then doc.Close()
If Not reader Is Nothing Then reader.Close()
End Try
Return isAdded
End Function