public bool WordToPDF(string sourcePath, string targetPath)

    {

      bool result = false;

      Microsoft.Office.Interop.Word.Application application = new Microsoft.Office.Interop.Word.Application();

      Document document = null;

      try

      {

       application.Visible = false;

       document = application.Documents.Open(sourcePath);

       document.ExportAsFixedFormat(targetPath, WdExportFormat.wdExportFormatPDF);

       result = true;

      }

      catch (Exception e)

      {

       Console.WriteLine(e.Message);

      }

      finally

      {

       document.Close();

      }

      return result;

    }

public bool WordToPdfWithWPS(string sourcePath, string targetPath)

    {

      WPS.ApplicationClass app = new WPS.ApplicationClass();

      WPS.Document doc = null;

      try

      {

       doc = app.Documents.Open(sourcePath, true, true, false, null, null, false, "", null, 100, 0, true, true, 0, true);

       doc.ExportPdf(targetPath, "", "");

      }

      catch (Exception ex)

      {

       Console.WriteLine(ex.Message);

       return false;

      }

      finally

      {

       doc.Close();

      }

      return true;

    }