Best method to extract text from PDF in asp.net C#

There are many ways to extract text from PDF.

• Microsoft IFilter interface and Adobe IFilter implementation
• iTextSharp
• PDFBox

Among those solutions using PDFBox is the best according to my experiences because,

• Using Adobe IFilter implementation need to have lot of other things set up in running machine like,
  • Windows 2000 or later
  • Adobe Acrobat or Reader 7.0.5+
  • IFilter COM wrapper class
• iTextSharp is opensource but can't be used in commercial products.

So the best solution is using PDFBox. It doesn't need other things installed on your machine.

PDFBox is a java PDF library and there is a .net version of PDFBox (It can be downloaded from here

Here is an example how to use PDFBox

using org.apache.pdfbox.pdmodel;
using org.apache.pdfbox.util;

// ...

private static string ExtractTextFromPdf(string path)
{
  PDDocument doc = null;
  try {
    doc = PDDocument.load(path)
    PDFTextStripper stripper = new PDFTextStripper();
    return stripper.getText(doc);
  }
  finally {
    if (doc != null) {
      doc.close();
    }
  }
}  

NOTE:

1. Following dll files of PDFBox library should be added to bin file of your project
   • commons-logging.dll
   • fontbox-1.8.9.dll
   • IKVM.OpenJDK.Text.dll
   • IKVM.OpenJDK.Util.dll
   • IKVM.Runtime.dll
2. Reference for following dll s should be added
   
   • IKVM.OpenJDK.Core.dll
   • IKVM.OpenJDK.SwingAWT.dll
   • pdfbox-1.8.9.dll