Replace the text in pdf document using itextSharp - itext

I want to replace a particular text in PDF document. I am currently using itextSharp library to play with PDF documents.
I had extracted the bytes from pdfdocument and then replaced that byte and then write the document again with the bytes but it is not working. In the below example I am trying to replace string 1234 with 5678
Any advise on how to perform this would be helpful.
PdfReader reader = new PdfReader(opf.FileNames[i]);
byte[] pdfbytes = reader.GetPageContent(1);
PdfString oldstring = new PdfString("1234");
PdfString newstring = new PdfString("5678");
byte[] byte1022 = oldstring.GetOriginalBytes();
byte[] byte1067 = newstring.GetOriginalBytes();
int position = 0;
for (int j = 0; j <pdfbytes.Length ; j++)
{
if (pdfbytes[j] == byte1022[0])
{
if (pdfbytes[j+1] == byte1022[1])
{
if (pdfbytes[j+2] == byte1022[2])
{
if (pdfbytes[j+3] == byte1022[3])
{
position = j;
break;
}
}
}
}
}
pdfbytes[position] = byte1067[0];
pdfbytes[position + 1] = byte1067[1];
pdfbytes[position + 2] = byte1067[2];
pdfbytes[position + 3] = byte1067[3];
File.WriteAllBytes(opf.FileNames[i].Replace(".pdf","j.pdf"), pdfbytes);

What makes you think 1234 is part of the page's content stream and not of a form XObject? Your code is never going to work in general if you don't parse all the resources of a page.
Also: I see GetPageContent(), but I don't see you using SetPageContent() anywhere. How are the changes ever going to be stored in the PdfReader object?
Moreover, I don't see you using PdfStamper to write the altered PdfReader contents to a file.
Finally: I'm to shy to quote the words of Leonard Rosenthol, Adobe's PDF Architect, but ask him, and he'll tell you personally that you shouldn't do what you're trying to do. PDF is NOT a format for editing.Read the intro of chapter 6 of the book I wrote on iText: http://www.manning.com/lowagie2/samplechapter6.pdf

Related

MalformedInputException: Input length = 1 while reading text file with Files.readAllLines(Path.get("file").get(0);

Why am I getting this error? I'm trying to extract information from a bank statement PDF and tally different bills for the month. I write the data from a PDF to a text file so I can get specific data from the file (e.g. ASPEN HOME IMPRO, then iterate down to what the dollar amount is, then read that text line to a string)
When the Files.readAllLines(Path.get("bankData").get(0) code is run, I get the error. Any thoughts why? Encoding issue?
Here is the code:
public static void main(String[] args) throws IOException {
File file = new File("C:\\Users\\wmsai\\Desktop\\BankStatement.pdf");
PDFTextStripper stripper = new PDFTextStripper();
BufferedWriter bw = new BufferedWriter(new FileWriter("bankData"));
BufferedReader br = new BufferedReader(new FileReader("bankData"));
String pdfText = stripper.getText(Loader.loadPDF(file)).toUpperCase();
bw.write(pdfText);
bw.flush();
bw.close();
LineNumberReader lineNum = new LineNumberReader(new FileReader("bankData"));
String aspenHomeImpro = "PAYMENT: ACH: ASPEN HOME IMPRO";
String line;
while ((line = lineNum.readLine()) != null) {
if (line.contains(aspenHomeImpro)) {
int lineNumber = lineNum.getLineNumber();
int newLineNumber = lineNumber + 4;
String aspenData = Files.readAllLines(Paths.get("bankData")).get(0); //This is the code with the error
System.out.println(newLineNumber);
break;
} else if (!line.contains(aspenHomeImpro)) {
continue;
}
}
}
So I figured it out. I had to check the properties of the text file in question (I'm using Eclipse) to figure out what the actual encoding of the text file was.
Then, when creating the file in the program, encode the text file to UTF-8 so that Files.readAllLines could read and grab the data I wanted to get.

Solution to upload image file via WCF service?

Being surfing for last 3-4 days downloading, running and fixing issues with available demo projects online, none of them work so far.
I need to upload an image using WCF webservice. Where from client side end I like to upload it by means of form (multipart/form-data), including some file description.
Any solution working with proper answer? My mind is really stacked overflow trying different solution. One which I initially have I am able to upload a text file where file gets created with some extra content in it. I need to upload image file.
------------cH2ae0GI3KM7GI3Ij5ae0ei4Ij5Ij5
Content-Disposition: form-data; name=\"Filename\"
testing file gets upload...
When I upload image file, the image file is empty.
Initial Code (one implantation), method by means of which I get the .txt file as above, in case of image its blank (or say corrupt don't know)
private string uplaodFile(Stream stream)
{
StreamReader sr = new StreamReader(stream);
int length = sr.ReadToEnd().Length;
byte[] buffer = new byte[length];
stream.Read(buffer, 0, length);
FileStream f = new FileStream(Path.Combine(HostingEnvironment.MapPath("~/Upload"), "test.png"), FileMode.OpenOrCreate);
f.Write(buffer, 0, buffer.Length);
f.Close();
stream.Close();
return "Recieved the image on server";
}
another;
public Stream FileUpload(string fileName, Stream stream)
{
string FilePath = Path.Combine(HostingEnvironment.MapPath("~/Upload"), fileName);
int length = 0;
using (FileStream writer = new FileStream(FilePath, FileMode.Create))
{
int readCount;
var buffer = new byte[8192];
while ((readCount = stream.Read(buffer, 0, buffer.Length)) != 0)
{
writer.Write(buffer, 0, readCount);
length += readCount;
}
}
return returnJson(new { resp_code = 302, resp_message = "occurred." });
}

Reading PDF document with iTextSharp creates string with repeating first page

I currently use iTextSharp to read in some PDF files and parse them by using the string I receive. I have encountered a strange behavior with some PDF files. When getting the string back of a for example 4 page PDF, the string is filled with the pages in the following order:
1 2 1 3 1 4
My code for reading the files is as follows:
using (PdfReader reader = new PdfReader(fileStream))
{
StringBuilder sb = new StringBuilder();
ITextExtractionStrategy strategy = new SimpleTextExtractionStrategy();
for (int page = 0; page < reader.NumberOfPages; page++)
{
string text = PdfTextExtractor.GetTextFromPage(reader, page + 1, strategy);
if (!string.IsNullOrWhiteSpace(text))
sb.Append(Encoding.UTF8.GetString(Encoding.Convert(Encoding.Default, Encoding.UTF8, Encoding.Default.GetBytes(text))));
}
Debug.WriteLine(sb.ToString());
}
Here is a link to a file with which this behaviour occurs:
https://onedrive.live.com/redir?resid=D9FEFF3BF45E05FD!1536&authkey=!AFLRlskAvlg89yY&ithint=file%2cpdf
Hope you guys can help me out!
Thanks to Chris Haas I found out was going wrong. The samples found online on how to use iTextSharp.Pdf are incorrect or incorrect for my implementation.
The SimpleTextExtractionStrategy needs to be instantiated for every page you try to read. Not doing this will multiply each previous page in the resulting string.
Also the line where the StringBuilder is being appended can be changed from:
sb.Append(Encoding.UTF8.GetString(Encoding.Convert(Encoding.Default, Encoding.UTF8, Encoding.Default.GetBytes(text))));
to
sb.Append(text);
Thus the following code gives the correct result:
using (PdfReader reader = new PdfReader(fileStream))
{
StringBuilder sb = new StringBuilder();
for (int page = 0; page < reader.NumberOfPages; page++)
{
string text = PdfTextExtractor.GetTextFromPage(reader, page + 1, new SimpleTextExtractionStrategy());
if (!string.IsNullOrWhiteSpace(text))
sb.Append(text);
}
Debug.WriteLine(sb.ToString());
}

iText not returning text contents of a PDF after first page

I am trying to use the iText library with c# to capture the text portion of pdf files.
I created a pdf from excel 2013 (exported) and then copied the sample from the web of how to use itext (added the lib ref to the project).
It reads perfectly the first page but it gets garbled info after that. It is keeping part of the first page and merging the info with the next page. The commented lines is when I was trying to solve the problem, the string "thePage" is recreated inside the for loop.
Here is the code. I can email the pdf to whoever can help with this issue.
Thanks in advance
public static string ExtractTextFromPdf(string path)
{
ITextExtractionStrategy its = new iTextSharp.text.pdf.parser.LocationTextExtractionStrategy();
using (PdfReader reader = new PdfReader(path))
{
StringBuilder text = new StringBuilder();
//string[] theLines;
//theLines = new string[COLUMNS];
//string thePage;
for (int i = 1; i <= reader.NumberOfPages; i++)
{
string thePage = "";
thePage = PdfTextExtractor.GetTextFromPage(reader, i, its);
string [] theLines = thePage.Split('\n');
foreach (var theLine in theLines)
{
text.AppendLine(theLine);
}
// text.AppendLine(" ");
// Array.Clear(theLines, 0, theLines.Length);
// thePage = "";
}
return text.ToString();
}
}
A strategy object collects text data and does not know if a new page has started or not.
Thus, use a new strategy object for each page.

Creating a PDF back page using Itext

I am currently using iText (Java) to create a PDF document.
This PDf document is meant to be a Businesscard to be printed.
This is part of my code:
public void write() throws DocumentException, FileNotFoundException, IOException {
String extension = ".pdf";
String file = "testerPDF";
String filename = file + extension;
Document doku = new Document(PageSize.A4, 10,20,50,150);
PdfWriter writer = PdfWriter.getInstance(doku, new FileOutputStream(new File(filename)));
doku.open();
Phrase textblock = new Phrase();
// jetzt durch den Vector iterarieren
for(int i = 0; i < vector.size(); i++) {
Chunk chunk=new Chunk((String)vector.get(i));
textblock.add(chunk);
}
doku.add(new Paragraph(textblock));
doku.close();
writer.close();
}
So I need now a way to also write a Back Page for this created PDF. In such a way that the document would look like a Business card on Paper.