OnDoc/OfficeToPDFConverter/Class1.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Runtime.InteropServices.ComTypes;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.Office.Interop.Word;
using Microsoft.Office.Interop.Excel;
using System.Linq.Expressions;

namespace OfficeToPDFConverter
{
    public class Converter
    {
        public string Convert_Word(string B64Word,string path)
        {
            Microsoft.Office.Interop.Word.Application w = new Microsoft.Office.Interop.Word.Application();

            try
            {
                Helper.clsFileHelper_Converter fh = new Helper.clsFileHelper_Converter();
                string outputfile = "";
                string inputfile = "";
                string tmpfilename = DateTime.Now.ToString("yyyyMMddhhmmss");
                outputfile = tmpfilename + ".pdf";
                inputfile = tmpfilename + ".tmp";
                inputfile = path + @"\" + inputfile;
                outputfile = path + @"\" + outputfile;

                fh.SaveBase64ToFile(B64Word, path);
                w.Documents.Open(FileName: inputfile.ToString(), ReadOnly: true);
                object oMissing = System.Reflection.Missing.Value;
                w.ActiveDocument.ExportAsFixedFormat(outputfile.ToString(), Microsoft.Office.Interop.Word.WdExportFormat.wdExportFormatPDF, false, Microsoft.Office.Interop.Word.WdExportOptimizeFor.wdExportOptimizeForPrint, Microsoft.Office.Interop.Word.WdExportRange.wdExportAllDocument, 0, 0, Microsoft.Office.Interop.Word.WdExportItem.wdExportDocumentContent, true, true, Microsoft.Office.Interop.Word.WdExportCreateBookmarks.wdExportCreateNoBookmarks, true, false, false);
                w.ActiveDocument.Saved = true;
                w.ActiveDocument.Close(SaveChanges: false);

                w.Quit(false);
                w = null;
                string b64 = fh.Base64FromFile(outputfile);
                System.IO.File.Delete(outputfile);
                return b64;
            }
            catch
            {
                return "";
            }
            finally
            {
                try { w.Quit(false); } catch { }
                w = null;
            }

        }
        public string Convert_Excel(string B64Word, string path)
        {
            Microsoft.Office.Interop.Excel.Application x = new Microsoft.Office.Interop.Excel.Application();
            try
            {
                Helper.clsFileHelper_Converter fh = new Helper.clsFileHelper_Converter();
                string outputfile = "";
                string inputfile = "";
                string tmpfilename = DateTime.Now.ToString("yyyyMMddhhmmss");
                outputfile = tmpfilename + ".pdf";
                inputfile = tmpfilename + ".tmp";
                inputfile = path + @"\" + inputfile;
                outputfile = path + @"\" + outputfile;

                fh.SaveBase64ToFile(B64Word, path);
                x.Workbooks.Open(inputfile);
                x.ActiveWorkbook.ExportAsFixedFormat(Microsoft.Office.Interop.Excel.XlFixedFormatType.xlTypePDF, outputfile.ToString(), Microsoft.Office.Interop.Excel.XlFixedFormatQuality.xlQualityStandard);
                x.ActiveWorkbook.Close(SaveChanges: false);
                x.Quit();
                x = null;
                string b64 = fh.Base64FromFile(outputfile);
                System.IO.File.Delete(outputfile);
                return b64;
            }
            catch {  return ""; }
            finally { try { x.Quit(); } catch { } x = null; }

        }
    }

}