Pdfsharp注释内容日语字体

Question

我已经编写了一个c＃代码以在带有标志的文本中添加注释，但是注释内容是日语，在程序执行后，当我看到注释内容是“4WASÕíóÈC/ U”某种其他语言时。

可以更改注释内容的字体以考虑日语

var CNNAnnot = new PdfTextAnnotation(); 
   CNNAnnot.Flags = PdfAnnotationFlags.Locked;
 CNNAnnot.Title = "Connector Details";
if (newConnector == true)
     {
   communicater = new synchronizer(newConnectorFinder);
    Invoke(communicater);
   CNNAnnot.Contents = "Connector Number : " + cNumber + " (New)" + Environment.NewLine;
                                            }
                                            else
  CNNAnnot.Contents = "Connector Number : " + cNumber + Environment.NewLine;                                               
  CNNAnnot.Contents += Environment.NewLine + "SC Name : " + SCName + Environment.NewLine;
  CNNAnnot.Contents += Environment.NewLine + "SM Name : " + SMName + Environment.NewLine;
}

CNNAnnot.Color = XColors.Green;
                                            CNNAnnot.Icon = PdfTextAnnotationIcon.Insert;
                                            option.Annotations.Add(CNNAnnot);
                                            var CNNrect = new XRect();
                                            xCoOrdinate = textStringBox.X;
                                            yCoOrdinate = textStringBox.Y;
                                            textWidth = textStringBox.Width;
                                            textHeight = textStringBox.Height;

                                                ConnectorLocationInSc.Add(cNumber, Math.Floor(xCoOrdinate).ToString() + ":" + Math.Floor(yCoOrdinate).ToString());

                                            CNNrect = gfx.Transformer.WorldToDefaultPage(new XRect(new XPoint(xCoOrdinate, yCoOrdinate), new XSize(0, 0)));
                                            CNNAnnot.Rectangle = new PdfRectangle(CNNrect);

The Annotation after execution