Meziantou.Framework

Reading and modifying

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PdfDocument.Open reads an existing document: every member of PdfDocument then works on it as on a document you create. Pages can be read, drawn on, added and removed; the metadata, the outline and the attachments can be changed; and the document is saved again.

var document = PdfDocument.Open(file);
var pageCount = document.Pages.Count;
var text = document.Pages[0].ExtractText();

What the reader supports

  • Cross-reference tables and streams, hybrid files, object streams, incremental updates and linearized files.
  • Every standard filter of the streams: FlateDecode and LZWDecode (with their predictors), ASCIIHexDecode, ASCII85Decode, RunLengthDecode, CCITTFaxDecode, JBIG2Decode, and DCTDecode and JPXDecode through the codecs of Meziantou.Framework.Imaging.
  • Encrypted documents of the standard security handler, with the user or the owner password.
  • Damaged files: a file whose cross-reference information is wrong is repaired by scanning it, a stream whose length is wrong ends where its data ends, and the damaged data of a filter (FlateDecode, ASCII85Decode, ASCIIHexDecode, a truncated row of a predictor) gives the bytes decoded before the damage.

The objects of a file are parsed when they are first used, not when the document is opened, and the document keeps the data of the file it was read from.

In this section

  • Opening documents: files, streams and arrays, passwords, read options and repaired files.
  • Extracting text: the text of a page, and search a document.
  • Modifying documents: stamp the pages, add and remove pages, full and incremental saves.
  • The object model: read and change the objects of a document directly.
  • Errors and limits: the exceptions, and how to open the files of untrusted users.
  • Managing pages: move, duplicate, remove and merge pages, page boxes, display coordinates, and stamp a page on others.
  • Extracting images: the images of a page, where they are, and their pixels.
  • Forms: create, read, fill and flatten the fields of an interactive form.