onepdfCookbook
onepdf cookbook
Short recipes for common OnePDF tasks, each with complete code you can copy.
Recipes
Add an image or a watermark to a PDFDraw a PNG or JPEG onto a page of an existing PDF in C#, stamp a translucent “DRAFT” across every page, and put a faint logo behind the content.Arabic and Hindi text in a PDFWrite Arabic (right to left, letters joined) and Hindi (conjuncts and vowel signs in place) into a PDF in C# with OnePdf.Layout, and read it back.Create PDF/AWrite PDF/A-2b and PDF/A-3u files in C# from documents made or edited with OnePDF, attach data to PDF/A-3, and check files from elsewhere first.Create PDF/UAGenerate a tagged PDF in C# that is PDF/UA-1 and PDF/A-2a in one file, and see what OnePDF refuses when a title or alternate text is missing.Decrypt or encrypt a PDFRemove the password from a PDF you are allowed to open, in C#, or encrypt one with AES-256, a password and permission flags, with OnePDF.Extract text from a PDFRead the text of every page of a PDF in C# in reading order, leave out running headers and footers, and keep the page layout when you need it, with OnePDF.Fill and flatten form fieldsList a PDF form’s fields, fill text fields and check boxes in C#, save the filled form, then flatten it so the values become part of the page, with OnePDF.Generate a PDF with tablesGenerate a multi-page PDF table in C# with OnePdf.Layout: column widths, striped rows, header and footer rows on every page, spans and page numbers.Merge PDFsMerge PDF files in C# with OnePDF, keeping bookmarks, links and form fields, merge PDFs held in memory, or append chosen pages to a file.Redact text in a PDFFind a name on every page of a PDF in C#, remove it from the content, cover the spot with a black box, and clear it from the metadata.Repair a damaged PDFOpen a damaged or truncated PDF in C#, see what OnePDF repaired, and save a clean copy, or reject damaged files outright with strict mode.Rotate, delete and reorder pagesRotate, delete, move and insert pages of an existing PDF in C# with OnePDF; bookmarks and links to deleted pages are repaired.Sign a PDF and verify its signaturesSign a PDF in C# with a certificate from a .pfx file, verify the signature against your own root, and see how a change after signing is reported.Split a PDFSplit a PDF into one file per page, or into chosen page ranges, in C# with OnePDF. Bookmarks, links and form fields go with their pages.Get words and their positionsRead every word on a PDF page with its bounding box in C#, group words into rows, and find the value printed next to a label, with OnePDF.