Windows
ComPDFKit PDF SDK
Guides

Annotations

 

In addition to its primary textual content, a PDF file can contain annotations that represent links, form elements, highlighting circles, textual notes, and so on. Each annotation is associated with a specific location on a page and may offer interactivity with the user. Annotations allow users to mark up and comment on PDFs without altering the original author's content.

ComPDFKit supports most annotation types defined in PDF Reference and provides APIs of annotation creation, properties access and modification, appearance setting and drawing.

 

Annotation Types

 

ComPDFKit supports all common annotation types:

- Note

- Link

- Free Text

- Shapes: Square, Circle, Line

- Markup: Highlight, Underline, Strikeout, Squiggly

- Stamp

- Ink

- Sound

 

These are standard annotations (as defined in the PDF Reference) that can be read and written by many apps, such as Adobe Acrobat and Apple Preview.