Add area annotation

Area annotation allows to mark up an area within the document page with a rectangle like shown at the picture below. 

There is an ability to specify the next properties for AreaAnnotation type:

  • BackgroundColor - describes area background color;
  • Box - defines annotation position at document page;
  • Opacity - allows to set annotation opacity;
  • PenColor - defines frame color;
  • PenStyle - defines frame line style (solid, dash, dot etc.);
  • PenWidth - defines frame line width in pixels.

Follow these steps to add Area annotation to document:

  • Instantiate Annotator object with input document path or stream;
  • Instantiate AreaAnnotation object with desired properties (position, page number, etc);
  • Call Add method and pass AreaAnnotation object;
  • Call Save method with resultant document path or stream.

The following code demonstrates how to add AreaAnnotation to the document:

using (Annotator annotator = new Annotator("input.pdf"))
{
	AreaAnnotation area = new AreaAnnotation
    {
     	BackgroundColor = 65535,
        Box = new Rectangle(100, 100, 100, 100),
        CreatedOn = DateTime.Now,
        Message = "This is area annotation",
        Opacity = 0.7,
        PageNumber = 0,
        PenColor = 65535,
        PenStyle = PenStyle.Dot,
        PenWidth = 3,
        Replies = new List<Reply>
        {
        	new Reply
            {
            	Comment = "First comment",
                RepliedOn = DateTime.Now
            },
            new Reply
            {
            	Comment = "Second comment",
                RepliedOn = DateTime.Now
            }
        }
    };
    annotator.Add(area);
    annotator.Save("result.pdf");
}

More resources

Advanced Usage Topics

To learn more about document annotating features, please refer to the advanced usage section.

GitHub Examples

You may easily run the code above and see the feature in action in our GitHub examples:

Free Online App

Along with full-featured .NET library we provide simple but powerful free Apps. You are welcome to annotate your PDF, DOC or DOCX, XLS or XLSX, PPT or PPTX, PNG and other documents with free to use online GroupDocs Annotation App.