1.通过NUget安装Spire.PDF

2.代码
//创建PdfDocument类的对象,并加载PDF文档
Spire.Pdf.PdfDocument doc = new Spire.Pdf.PdfDocument();
doc.LoadFromFile("scanOutReal.PDF");
//静默打印PDF文档
doc.PrintSettings.PrintController = new StandardPrintController();
doc.Print();
3.八种打印方式参考
https://blog.csdn.net/Eiceblue/article/details/78422734