public void printPDF(string pdfPath)
        {
            PrintDocument printDoc = new PrintDocument();
            printDoc.PrinterSettings.PrinterName = PrinterName;
            printDoc.PrintController = new System.Drawing.Printing.StandardPrintController();
            if (!printDoc.PrinterSettings.IsValid)
            {
                throw new Exception("错误:找不到打印机");
            }

            //System.Drawing.Printing.PrintDocument pd = new System.Drawing.Printing.PrintDocument();
            Process processInstance = new Process();
            ProcessStartInfo startInfo = new ProcessStartInfo();
            startInfo.UseShellExecute = true;
            startInfo.Verb = "Print";
            startInfo.CreateNoWindow = true;
            startInfo.WindowStyle = ProcessWindowStyle.Hidden;

            startInfo.Arguments = @"/p /h /" + pdfPath + @"/" + PrinterName + "/";
            startInfo.FileName = pdfPath;
            try
            {
                processInstance.StartInfo = startInfo;
                processInstance.Start();
            }
            catch (Exception ex)
            {
                throw new Exception(ex.ToString());
            }
            finally
            {
                processInstance.Dispose();
                processInstance.Close();
            }
        }