.NET APIs to annotate and export annotated documents

Annotate any PDF, DOCX, XLSX and PPTX documents

Multiple markup and commenting tools

Reply based comments

Highlight Text Annotation

Custom stamp Annotation

Threading in comments

Simultaneous document annotations by multiple users

Save annotations in different objects like JSON files, Databases or merge with original file

Export annotations to separate PDF or Word file

Import Annotations

Abstract storage option – achieve it by using implemented interface provided by API

User Management – Abstract-ready user management

Annotation Compatibility - Annotations added are compatible with native PDF annotations

Metered licensing

Comparison Matrix

GroupDocs.Annotation for .NET VS A.nnotate and PDF Annotator

Core Annotations – markup and commenting tools

• Area Annotation – Mark an area for annotation in form of notes. Area can be a line, paragraph or portion of document
• Point Annotation – attach comments to any point
• Text Annotation – add explanation to any selected text

 // 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);
// Export annotation and save output file
CommonUtilities.SaveOutputDocument("input.pdf", annotations, DocumentType.Pdf);

• Strikeout / Underline Annotation – mark up text or revision instructions by editors with Strikeout or underline
• Text replacement -Replace selected text
• Text and Area redaction – blackout selected text and area within the document
• Polyline – draw shapes and lines.
• Pointer/arrow – attach arrows with notes
• Watermark – add a watermark
• Ruler or Distance Annotation – measure the distance between objects
• Undo/redo – cancel or reverse annotations