word to pdf
Microsoft.Office.Interop.Word.Application appWord = new Microsoft.Office.Interop.Word.Application();
Microsoft.Office.Interop.Word.Document wordDocument = appWord.Documents.Open(fileName);
string saveFileName = Path.GetDirectoryName(fileName);
saveFileName = Path.Combine(Path.GetDirectoryName(fileName), Path.GetFileNameWithoutExtension(fileName) + ".pdf");
wordDocument.ExportAsFixedFormat(saveFileName, Microsoft.Office.Interop.Word.WdExportFormat.wdExportFormatPDF);
appWord.Documents.Close();
appWord.Quit();
return saveFileName;