使用PDFsharp和MigraDoc写入然后从PDF中读取

我正在尝试为我们的PDF生成例程编写验证码，而我很难通过PDFsharp从使用MigraDoc创建的文件中提取文本 . ExtractText代码适用于其他PDF，但不适用于我使用MigraDoc生成的PDF（请参阅下面的代码 . ）

关于我做错的任何提示？

//Create the Doc
var doc = new MigraDoc.DocumentObjectModel.Document();
doc.Info.Title = "VerifyReadWrite";
var section = doc.AddSection();
section.AddParagraph("ABCDEF abcdef");

//Render the PDF
var renderer = new PdfDocumentRenderer(true);
var pdf = new PdfDocument();
renderer.PdfDocument = pdf;
renderer.Document = doc;
renderer.RenderDocument();
var msOut = new MemoryStream();
pdf.Save(msOut, true);
var pdfBytes = msOut.ToArray();

//Read the PDF into PdfSharp
var ms = new MemoryStream(pdfBytes);
var pdfRead = PdfSharp.Pdf.IO.PdfReader.Open(ms, PdfDocumentOpenMode.ReadOnly);
var segments = pdfRead.Pages[0].ExtractText().ToList();

结果如下：

segment [0] = "\0$\0%\0&\0'\0(\0)"
段[1] = "\0D\0E\0F\0G\0H\0I"

我希望看到：

segment [0] = "ABCDEF"
段[1] = "abcdef"

我在这里使用ExtractText代码：C# Extract text from PDF using PdfSharp

除了使用MigraDoc生成的PDF之外，它的效果非常好 .

public static IEnumerable<string> ExtractText(this PdfPage page)
    {
        var content = ContentReader.ReadContent(page);
        var text = content.ExtractText();
        return text.Select(x => x.Trim());
    }

    public static IEnumerable<string> ExtractText(this CObject cObject)
    {
        if (cObject is COperator)
        {
            var cOperator = (COperator) cObject;
            if (cOperator.OpCode.Name == OpCodeName.Tj.ToString() ||
                cOperator.OpCode.Name == OpCodeName.TJ.ToString())
            {
                foreach (var cOperand in cOperator.Operands)
                    foreach (var txt in ExtractText(cOperand))
                        yield return txt;
            }
        }
        else
        {
            var sequence = cObject as CSequence;
            if (sequence != null)
            {
                var cSequence = sequence;
                foreach (var element in cSequence)
                    foreach (var txt in ExtractText(element))
                        yield return txt;
            }
            else if (cObject is CString)
            {
                var cString = (CString) cObject;
                yield return cString.Value;
            }
        }
    }