GroupDocs.Annotation for .NET is a lightweight, flexible library for working with annotations in documents across Windows, Linux, and macOS. Its simple API helps you keep data on‑premises, control resource usage, and tailor annotation workflows to your needs.
Work with a wide range of annotation types, including Text, Polyline, Area, Underline, Point, Watermark, Arrow, Ellipse, Text Replacement, Distance, Text Field, and Redaction. The API supports popular document formats such as PDF, HTML, Microsoft Word, Excel, PowerPoint, Visio, Outlook emails, images, metafiles, CAD drawings, and more. Generate page thumbnails and import/export annotations to and from PDF files.
Use the library to add, edit, extract, and delete annotations; rotate pages; generate thumbnails; and more. It also provides a comprehensive set of data objects to customize annotation properties across all supported formats.
Getting started is simple: apply a license, load a file, manipulate annotations (add/edit/extract/delete), and save the result. For details, see the product documentation and sample projects.
GroupDocs.Annotation is regularly updated and supported. Share your questions, ideas, and feature requests—we actively incorporate customer feedback into new releases.
Following is an overview of GroupDocs.Annotation for .NET:
GroupDocs.Annotation for .NET supports popular document file formats including Microsoft Office, PDF, images, and more.
GroupDocs.Annotation for .NET supports the following operating systems, frameworks, and package managers:
GroupDocs.Annotation for .NET lets you work with many annotation types to streamline collaboration. Use area annotations (mark a rectangular region and add notes), point annotations (attach comments at any point in a document), text annotations (comment on selected text), strikeout/underline annotations, polyline annotations (draw shapes and freehand lines), arrow annotations (pointer with comments), ellipse annotations (display text inside an ellipse), distance annotations (draw a line representing distance between objects), link annotations (add web links), and watermark annotations (add stamps or watermarks).
GroupDocs.Annotation// Initialize list of AnnotationInfo
List<AnnotationInfo> annotations = new List<AnnotationInfo>();
// Initialize text annotation
AnnotationInfo textAnnotation = new AnnotationInfo
{
Box = new Rectangle((float)265.44, (float)153.86, 206, 36), Type = AnnotationType.Text
};
// Add annotation to list
annotations.Add(textAnnotation);
// Get input file stream
Stream inputFile = new FileStream("D:/input.pdf", FileMode.Open, File
.ReadWrite);
// Export annotation and save output file
CommonUtilities.SaveOutputDocument(inputFile, annotations, DocumentType.Pdf);
GroupDocs.Annotation