Ich habe das Wort im PDF-Format mithilfe des Codes in der Antwort auf die folgende Frage hervorgehoben: [Hervorheben von Wörtern in einem PDF mit itextsharp, wobei das hervorgehobene Wort im Browser nicht angezeigt wird]2

Aber ich habe "Eine Zahl ist außerhalb des Bereichs Fehler" beim Öffnen dieses pdf.

   private void hightlightPDFText()
{
    try
    {
        string[] highlightText = new string[] { "EXTENSIONAL", "geology" };
        string inputFile = Server.MapPath("~/pdf/") + "101111j174754572003tb00036x.pdf";
        string outputFile = Server.MapPath("~/pdf/") + "101111j174754572003tb00036x_Highlighted.pdf";
        // get input document            
        highlightPDFAnnotation(inputFile, outputFile, highlightText);
    }
    catch (Exception ex)
    {
        Response.Write(ex.Message);
    }
}
private void highlightPDFAnnotation(string inputFile, string outputFile, string[] highlightText)
{
    try
    {
        PdfReader reader = new PdfReader(inputFile);

        using (FileStream fs = new FileStream(outputFile, FileMode.Create, FileAccess.Write, FileShare.None))
        {
            using (PdfStamper stamper = new PdfStamper(reader, fs))
            {
                myLocationTextExtractionStrategy strategy = new myLocationTextExtractionStrategy();
                int pageCount = reader.NumberOfPages;
                for (int pageno = 1; pageno <= pageCount; pageno++)
                {


                    string currentText = PdfTextExtractor.GetTextFromPage(reader, pageno, strategy);
                    for (int i = 0; i < highlightText.Length; i++)
                    {
                        List<iTextSharp.text.Rectangle> MatchesFound = strategy.GetTextLocations(highlightText[i].Trim(), StringComparison.CurrentCultureIgnoreCase);
                        foreach (Rectangle rect in MatchesFound)
                        {
                            float[] quad = { rect.Left, rect.Bottom, rect.Right, rect.Bottom, rect.Left, rect.Top, rect.Right, rect.Top };
                            //Create our hightlight
                            PdfAnnotation highlight = PdfAnnotation.CreateMarkup(stamper.Writer, rect, null, PdfAnnotation.MARKUP_HIGHLIGHT, quad);
                            //Set the color
                            highlight.Color = BaseColor.YELLOW;

                            PdfAppearance appearance = PdfAppearance.CreateAppearance(stamper.Writer, rect.Width, rect.Height);
                            PdfGState state = new PdfGState();
                            state.BlendMode = new PdfName("Multiply");
                            appearance.SetGState(state);
                            appearance.Rectangle(0, 0, rect.Width, rect.Height);
                            appearance.SetColorFill(BaseColor.YELLOW);
                            appearance.Fill();
                            highlight.SetAppearance(PdfAnnotation.APPEARANCE_NORMAL, appearance);
                            stamper.AddAnnotation(highlight, pageno);
                        }
                    }
                }
            }
        }
        reader.Close();

        File.Copy(outputFile, inputFile, true);
        File.Delete(outputFile);
    }
    catch (Exception ex)
    {
        throw;
    }

}