How to extract PDF pages with highlighted text

Hello Greg,

To accomplish the task, iterate through the pages in the source document and check if the PdfPage.Annotations collection contains PdfTextMarkupAnnotation objects. If so, extract this page to a new document using the PdfDocumentProcessor.Document.Pages.Add method.
Here is a sample code snippet that demonstrates this solution:

C#
using (PdfDocumentProcessor source = new PdfDocumentProcessor())
{
        source.LoadDocument(sourceFile);
        List<int> highlightedPageNumbers = new List<int>();
        var pages = source.Document.Pages;
        for (int i = 0; i < pages.Count; i++)
        {
            PdfPage page = pages[i];
            var textMarkupAnnotations = page.Annotations.OfType<PdfTextMarkupAnnotation>();
            if (textMarkupAnnotations.Count() > 0)
                highlightedPageNumbers.Add(i);
        }
        if (highlightedPageNumbers.Count == 0) return;
        using (PdfDocumentProcessor target = new PdfDocumentProcessor())
        {
            target.CreateEmptyDocument("HighlightedPages.pdf");
            foreach (int pageIndex in highlightedPageNumbers)
                target.Document.Pages.Add(pages[pageIndex]);
        }

}

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