PdfPig

PdfPig supports reading text and content from PDF files. It also supports basic PDF file creation.

Installation

The package is available via the releases tab or from Nuget:

https://www.nuget.org/packages/PdfPig/

Or from the package manager console:

> Install-Package PdfPig

While the version is below 1.0.0 minor versions will change the public API without warning (SemVer will not be followed until 1.0.0 is reached).

Get Started

See the wiki for more examples

Reading text from a PDF

The simplest usage at this stage is to open a document, reading the words from every page:

// using UglyToad.PdfPig.DocumentLayoutAnalysis.TextExtractor;
// using UglyToad.PdfPig.DocumentLayoutAnalysis.WordExtractor;
using (PdfDocument document = PdfDocument.Open(@"C:\Documents\document.pdf"))
{
    foreach (Page page in document.GetPages())
    {
        string text = ContentOrderTextExtractor.GetText(page);
        IEnumerable<Word> words = page.GetWords(NearestNeighbourWordExtractor.Instance);
    }
}

You should not use page.Text directly, unless you know what you're doing. The Text property preserves the internal content order which is rarely ever the text in the order you want.

These layout analysis tools should get you the text you want in most cases.

Create PDF Document

To create documents use the class PdfDocumentBuilder. The Standard 14 fonts provide a quick way to get started:

PdfDocumentBuilder builder = new PdfDocumentBuilder();

PdfPageBuilder page = builder.AddPage(PageSize.A4);

// Fonts must be registered with the document builder prior to use to prevent duplication.
PdfDocumentBuilder.AddedFont font = builder.AddStandard14Font(Standard14Font.Helvetica);

page.AddText("Hello World!", 12, new PdfPoint(25, 700), font);

byte[] documentBytes = builder.Build();

File.WriteAllBytes(@"C:\git\newPdf.pdf", documentBytes);

The output is a 1 page PDF document with the text "Hello World!" in Helvetica near the top of the page:

Each font must be registered with the PdfDocumentBuilder prior to use enable pages to share the font resources. Only Standard 14 fonts and TrueType fonts (.ttf) are supported.

Document creation supports very limited changes to existing PDF documents. However it does not support any of the following:

• Editing forms
• Copying or changing annotations, metadata or document structure data
• Adding or removing text with existing fonts

Advanced Document Extraction

In this example a more advanced document extraction is performed. PdfDocumentBuilder is used to create a copy of the pdf with debug information (bounding boxes and reading order) added.

//using UglyToad.PdfPig;
//using UglyToad.PdfPig.DocumentLayoutAnalysis.PageSegmenter;
//using UglyToad.PdfPig.DocumentLayoutAnalysis.ReadingOrderDetector;
//using UglyToad.PdfPig.DocumentLayoutAnalysis.WordExtractor;
//using UglyToad.PdfPig.Fonts.Standard14Fonts;
//using UglyToad.PdfPig.Writer;


var sourcePdfPath = "";
var outputPath = "";
var pageNumber = 1;
using (var document = PdfDocument.Open(sourcePdfPath))
{
    var builder = new PdfDocumentBuilder { };
    PdfDocumentBuilder.AddedFont font = builder.AddStandard14Font(Standard14Font.Helvetica);
    var pageBuilder = builder.AddPage(document, pageNumber);
    pageBuilder.SetStrokeColor(0, 255, 0);
    var page = document.GetPage(pageNumber);

    var letters = page.Letters; // no preprocessing

    // 1. Extract words
    var wordExtractor = NearestNeighbourWordExtractor.Instance;

    var words = wordExtractor.GetWords(letters);

    // 2. Segment page
    var pageSegmenter = DocstrumBoundingBoxes.Instance;

    var textBlocks = pageSegmenter.GetBlocks(words);

    // 3. Postprocessing
    var readingOrder = UnsupervisedReadingOrderDetector.Instance;
    var orderedTextBlocks = readingOrder.Get(textBlocks);

    // 4. Add debug info - Bounding boxes and reading order
    foreach (var block in orderedTextBlocks)
    {
        var bbox = block.BoundingBox;
        pageBuilder.DrawRectangle(bbox.BottomLeft, bbox.Width, bbox.Height);
        pageBuilder.AddText(block.ReadingOrder.ToString(), 8, bbox.TopLeft, font);
    }

    // 5. Write result to a file
    byte[] fileBytes = builder.Build();
    File.WriteAllBytes(outputPath, fileBytes); // save to file
}

See Document Layout Analysis for more information on advanced document analysing.

See Export for more advanced tooling to analyse document layouts.

Usage

PdfDocument

The PdfDocument class provides access to the contents of a document loaded either from file or passed in as bytes. To open from a file use the PdfDocument.Open static method:

using UglyToad.PdfPig;
using UglyToad.PdfPig.Content;

using (PdfDocument document = PdfDocument.Open(@"C:\my-file.pdf"))
{
	int pageCount = document.NumberOfPages;

	// Page number starts from 1, not 0.
	Page page = document.GetPage(1);

	decimal widthInPoints = page.Width;
	decimal heightInPoints = page.Height;

	string text = page.Text;
}

This is the beginning of the README. Read the rest at the original. Read the full README ↗