Annotate documents with GroupDocs.Annotation Leave feedback
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GroupDocs.Annotation adds review markup to documents — areas, arrows, highlights, strikeouts, text fields, watermarks and threaded replies — and reads back the annotations already on a file. It is the API behind a document review or collaboration feature.
An area annotation boxes a region of a page and attaches a comment to it. Box is the rectangle in points, and PageNumber is zero-based.
using GroupDocs.Annotation;
using GroupDocs.Annotation.Models;
using GroupDocs.Annotation.Models.AnnotationModels;
using (Annotator annotator = new Annotator("contract.pdf"))
{
AreaAnnotation area = new AreaAnnotation
{
Box = new Rectangle(100, 100, 200, 100),
BackgroundColor = 65535,
Message = "Please confirm these figures",
PageNumber = 0,
Opacity = 0.7
};
annotator.Add(area);
annotator.Save("annotation-add-area.pdf");
}
contract.pdf is the sample file used in this example. Click here to download it.
Binary file (PDF, 130 KB)
NoteColours are 32-bit integers, notColorvalues —65535is yellow.PageNumbercounts from zero, so the first page is0.
A highlight annotation is bounded by four corner Points rather than a rectangle, because a highlight can follow text that wraps across lines and is not always a neat box.
using System.Collections.Generic;
using GroupDocs.Annotation;
using GroupDocs.Annotation.Models;
using GroupDocs.Annotation.Models.AnnotationModels;
using (Annotator annotator = new Annotator("contract.pdf"))
{
HighlightAnnotation highlight = new HighlightAnnotation
{
// Corner points of the region to highlight
Points = new List<Point>
{
new Point(80, 730),
new Point(240, 730),
new Point(80, 710),
new Point(240, 710)
},
BackgroundColor = 65535,
Message = "Check this clause against the contract",
PageNumber = 0,
Opacity = 0.5
};
annotator.Add(highlight);
annotator.Save("annotation-highlight.pdf");
}
contract.pdf is the sample file used in this example. Click here to download it.
Binary file (PDF, 132 KB)
Get returns the annotations already on a document — how you load an existing review into your own UI.
using System;
using System.Collections.Generic;
using GroupDocs.Annotation;
using GroupDocs.Annotation.Models;
using GroupDocs.Annotation.Models.AnnotationModels;
// Annotate first, so there is something to read back
using (Annotator annotator = new Annotator("contract.pdf"))
{
annotator.Add(new AreaAnnotation
{
Box = new Rectangle(100, 100, 200, 100),
Message = "Please confirm these figures",
PageNumber = 0
});
annotator.Save("annotation-extract.pdf");
}
using (Annotator annotator = new Annotator("annotation-extract.pdf"))
{
List<AnnotationBase> annotations = annotator.Get();
Console.WriteLine("Annotations found: " + annotations.Count);
foreach (AnnotationBase annotation in annotations)
{
Console.WriteLine(annotation.GetType().Name
+ " on page " + annotation.PageNumber
+ ": " + annotation.Message);
}
}
contract.pdf is the sample file used in this example. Click here to download it.
Binary file (PDF, 130 KB)
GroupDocs.Annotation supports eighteen annotation types, threaded replies for multi-round review, updating and removing existing annotations, importing and exporting annotations as XML, page previews, and document version history.
- GroupDocs.Annotation for .NET documentation — the full product guide
- Supported file formats
- API reference
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