Annotate Text or Images in Documents

‎Empower your .NET Applications to Add, Edit & Remove all Popular Annotation Types from over 50 document formats for an Easier & Efficient Collaboration.‎

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GroupDocs.Annotation for .NET is a comprehensive set of APIs that helps you build document annotation management applications in C#, ASP.NET and other related .NET technologies. You can create and work with all popular annotation types, such as area, point, text, ellipse, link, underline, polyline, arrow, distance, watermark, image etc for PDF, HTML, Microsoft Office Word, Excel spreadsheets, PowerPoint presentations, Visio, images, CAD drawing and various other formats. The document annotator library allows you to export documents after adding annotations, comments or highlighted notes back to its original format. It also gives you a handy set of data objects through which you can customize annotations as per your requirements.

GroupDocs.Annotation for .NET Features

Add, Edit & Remove Annotations and Replies

Export Annotations to Document

Metered License – Controlled Billing by Paying According to API Usage

Single Function Call to Fetch All Annotations of a Document

Assign Value to Point Annotation or Move Existing Point Value

Add Link Annotation to PDF, Word & PowerPoint Slides

Set Background Color of an Annotation or Remove all the Annotations from Document‎

Annotate PDF files with Accuracy – Get Image Representation of PDF Document & Cache Page Previews

Get Text Coordinates of Text Annotation in Image Representation of Document

Link User Comments to Area Annotation & Support for Nested Comments

Use Arrow Annotation for pointing to Particular Content

Use Distance Annotation to Draw a Line that Represents Distance among Objects

Point based Annotation that when Clicked Pops Window to Add Comments

Create a Connected Sequence of Line Segments Created as a Polyline Annotation

Create Straight Line Segments, Arc Segments, or a combination of the both

Mark Document Areas Proposed for Redaction

Add Image Annotation to PDF, Diagrams, Word, Excel, Presentations & Images

Add Text Field & Text based Stamp or Watermark in Document

Strike Through, Underline or Replace Particular Text in a Document

Resize Annotation by assigning new Height & Width Parameters

Get Thumbnails of Document Pages. Manage a Variety of Annotated Docs for Images & Diagrams

Export Annotations to & Work with Multi-page TIFF files

Adjust Vertical and Horizontal Alignment for Watermark Annotation

Add Text Horizontal Alignment for Text Field

Get information about document text lines (text, width, height, indents)

Support for Multiple Types of Annotation

GroupDocs.Annotation for .NET enables you to work with various types of annotations. This gives freedom and ease of communication while collaborating with your team on tasks. You can use annotations, such as, area annotation (mark an area as rectangle and add notes to it), point annotation (stick comments at any point in document), text annotation (add comment to selected text), strikeout/underline annotation (applied to a paragraph), polyline annotation (draw shapes and freehand lines), arrow annotation (arrow pointer with attached comments), ellipse annotation (display text inside the ellipse), distance annotation (draw a line that represents distance among objects), link annotation (add web links to supported document formats), and watermark annotation (text stamp or watermark can be added in document).‎

// 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
// Get input file stream
Stream inputFile = new FileStream("D:/input.pdf", FileMode.Open, File
// Export annotation and save output file
CommonUtilities.SaveOutputDocument(inputFile, annotations, DocumentType.Pdf);

Support and Learning Resources

GroupDocs.Annotation offers document viewing APIs for other popular development environments