以下是解决我问题的代码：

Here is the code which solved my issue :

PDActionRemoteGoTo remoteGoto = new PDActionRemoteGoTo();
PDComplexFileSpecification fileDesc = new PDComplexFileSpecification();
fileDesc.setFile(System.IO.Path.GetFileName(filePath));
                            remoteGoto.setOpenInNewWindow(true);
                            remoteGoto.setFile(fileDesc);
                            txtLink.setAction(remoteGoto);
 txtLink.setRectangle(rect);
 page.getAnnotations().add(txtLink);