この記事では、PDFビューアーの機能、利点、制限とその克服方法を探ります。

// C# code for annotating a PDF file using IronPDF.

// Import IronPDF library
using IronPdf;

// Example method to demonstrate PDF annotation
public static void AnnotatePdf(string inputFilePath, string outputFilePath)
{
    // Create a new instance of the IronPdfRenderer
    var pdfRenderer = new IronPdf.PdfDocument();

    // Load an existing PDF document
    var pdfDocument = PdfDocument.FromFile(inputFilePath);

    // Access a specific page in the PDF
    var pdfPage = pdfDocument.Pages[0];

    // Add a simple text annotation on the top-right corner of the page
    pdfPage.Annotations.AddTextAnnotation("Sample Annotation", new PdfPoint(500, 750));

    // Highlight text at specified positions (e.g., positions can be obtained from coordinate mapping or OCR)
    pdfPage.Annotations.HighlightText(PdfMarker.CreateRectangle(100, 500, 200, 50), System.Drawing.Color.Yellow);

    // Save the annotated PDF to a new file
    pdfDocument.SaveAs(outputFilePath);
}

' C# code for annotating a PDF file using IronPDF.

' Import IronPDF library
Imports IronPdf

' Example method to demonstrate PDF annotation
Public Shared Sub AnnotatePdf(ByVal inputFilePath As String, ByVal outputFilePath As String)
	' Create a new instance of the IronPdfRenderer
	Dim pdfRenderer = New IronPdf.PdfDocument()

	' Load an existing PDF document
	Dim pdfDocument = PdfDocument.FromFile(inputFilePath)

	' Access a specific page in the PDF
	Dim pdfPage = pdfDocument.Pages(0)

	' Add a simple text annotation on the top-right corner of the page
	pdfPage.Annotations.AddTextAnnotation("Sample Annotation", New PdfPoint(500, 750))

	' Highlight text at specified positions (e.g., positions can be obtained from coordinate mapping or OCR)
	pdfPage.Annotations.HighlightText(PdfMarker.CreateRectangle(100, 500, 200, 50), System.Drawing.Color.Yellow)

	' Save the annotated PDF to a new file
	pdfDocument.SaveAs(outputFilePath)
End Sub