Example of Annotations in ASP.NET Core PDF Viewer Control
This sample demonstrates the creation of all the types of annotations in the PDF Viewer such as Text Markup, Shapes, Measurements, Free text, Stamps, Handwritten signature, ink, and sticky notes. Also, we can customize the added annotation or we can include new annotations through user interaction from the PDF Viewer.
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More information on adding annotation programmatically can be found in this documentation section .