Convert PDF file to TEXT file

String tempFolderPath = Path.GetTempPath();
                       StreamWriter writeTextFile = File.CreateText(tempFolderPath + "content.txt");
            writeTextFile.WriteLine(TransformPdfToText(tempFolderPath + "coalmar100604.pdf"));
            writeTextFile.Close();
 

private static string TransformPdfToText(string SourceFile)
        {
            string content = "";
            PDDocument doc = PDDocument.load(SourceFile);
            PDFTextStripper stripper = new PDFTextStripper();
         
            try
            {
                content = stripper.getText(doc);

                doc.close();
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            finally
            {
                doc.close();
            }
            return content;
        }