How do I convert Word files to PDF programmatically?

Question

I have found several open-source/freeware programs that allow you to convert .doc files to .pdf files, but they're all of the application/printer driver variety, with no SDK attached.

I have found several programs that do have an SDK allowing you to convert .doc files to .pdf files, but they're all of the proprietary type, $2,000 a license or thereabouts.

Does anyone know of any clean, inexpensive (preferably free) programmatic solution to my problem, using C# or VB.NET?

Thanks!

Answer 1

Use a foreach loop instead of a for loop - it solved my problem.

int j = 0;
foreach (Microsoft.Office.Interop.Word.Page p in pane.Pages)
{
    var bits = p.EnhMetaFileBits;
    var target = path1 +j.ToString()+  "_image.doc";
    try
    {
        using (var ms = new MemoryStream((byte[])(bits)))
        {
            var image = System.Drawing.Image.FromStream(ms);
            var pngTarget = Path.ChangeExtension(target, "png");
            image.Save(pngTarget, System.Drawing.Imaging.ImageFormat.Png);
        }
    }
    catch (System.Exception ex)
    {
        MessageBox.Show(ex.Message);  
    }
    j++;
}

Here is a modification of a program that worked for me. It uses Word 2007 with the Save As PDF add-in installed. It searches a directory for .doc files, opens them in Word and then saves them as a PDF. Note that you'll need to add a reference to Microsoft.Office.Interop.Word to the solution.

using Microsoft.Office.Interop.Word;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;

...

// Create a new Microsoft Word application object
Microsoft.Office.Interop.Word.Application word = new Microsoft.Office.Interop.Word.Application();

// C# doesn't have optional arguments so we'll need a dummy value
object oMissing = System.Reflection.Missing.Value;

// Get list of Word files in specified directory
DirectoryInfo dirInfo = new DirectoryInfo(@"\\server\folder");
FileInfo[] wordFiles = dirInfo.GetFiles("*.doc");

word.Visible = false;
word.ScreenUpdating = false;

foreach (FileInfo wordFile in wordFiles)
{
    // Cast as Object for word Open method
    Object filename = (Object)wordFile.FullName;

    // Use the dummy value as a placeholder for optional arguments
    Document doc = word.Documents.Open(ref filename, ref oMissing,
        ref oMissing, ref oMissing, ref oMissing, ref oMissing, ref oMissing,
        ref oMissing, ref oMissing, ref oMissing, ref oMissing, ref oMissing,
        ref oMissing, ref oMissing, ref oMissing, ref oMissing);
    doc.Activate();

    object outputFileName = wordFile.FullName.Replace(".doc", ".pdf");
    object fileFormat = WdSaveFormat.wdFormatPDF;

    // Save document into PDF Format
    doc.SaveAs(ref outputFileName,
        ref fileFormat, ref oMissing, ref oMissing,
        ref oMissing, ref oMissing, ref oMissing, ref oMissing,
        ref oMissing, ref oMissing, ref oMissing, ref oMissing,
        ref oMissing, ref oMissing, ref oMissing, ref oMissing);

    // Close the Word document, but leave the Word application open.
    // doc has to be cast to type _Document so that it will find the
    // correct Close method.                
    object saveChanges = WdSaveOptions.wdDoNotSaveChanges;
    ((_Document)doc).Close(ref saveChanges, ref oMissing, ref oMissing);
    doc = null;
}

// word has to be cast to type _Application so that it will find
// the correct Quit method.
((_Application)word).Quit(ref oMissing, ref oMissing, ref oMissing);
word = null;