How to achieve later binding in C # for Microsoft.office.interop.word?

Question

I want to get the latest binding for the following lines of code that use early binding. How can I achieve this in C #?

When I removed the Microsoft.office.interop.word link, I get some errors that are mentioned in the comments in the following code. Folloowing is the code that I use to convert a Word document to pdf.

    Type wordType = Type.GetTypeFromProgID("Word.Application");

        dynamic Word = Activator.CreateInstance(wordType);


        object oMissing = System.Reflection.Missing.Value;


        DirectoryInfo dirInfo = new DirectoryInfo(@"\\server\folder");
        FileInfo wordFile = new FileInfo(fileName);

        Word.Visible = false;
        Word.ScreenUpdating = false;

        Object filename = (Object)wordFile.FullName;


        var doc = Word.Documents.Open(ref filename);
        doc.Activate();

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

    /*Getting an error in WdSaveFormat */ 
        object fileFormat = WdSaveFormat.wdFormatPDF;



        doc.SaveAs(ref outputFileName, ref fileFormat);



        /*Getting an error in WdSaveOptions */       
        object saveChanges = WdSaveOptions.wdDoNotSaveChanges;

    /*Getting an error in _Document*/ 
        ((_Document)doc).Close(ref saveChanges);
        doc = null;


        Word.Quit();


        MessageBox.Show("Successfully converted");

Answer 1

Made the following changes: now it works fine.

    Type wordType = Type.GetTypeFromProgID("Word.Application");

    dynamic Word = Activator.CreateInstance(wordType);


    object oMissing = System.Reflection.Missing.Value;


    DirectoryInfo dirInfo = new DirectoryInfo(@"\\server\folder");
    FileInfo wordFile = new FileInfo(fileName);

    Word.Visible = false;
    Word.ScreenUpdating = false;

    Object filename = (Object)wordFile.FullName;

    var doc = Word.Documents.Open(ref filename);
    doc.Activate();

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

/*in the WdSaveFormat enum, 17 is the value for pdf format*/ 
    object fileFormat = 17;


    doc.SaveAs(ref outputFileName, ref fileFormat);

 /in the   WdSaveOptions enum, 0 is for Do not save pending changes.*/
    object saveChanges = 0;

    doc.Close(ref saveChanges);
    doc = null;

    Word.Quit();

    MessageBox.Show("Successfully converted");

Answer 2

Historically, late binding was possible (and still!) With a reflection:

object word = ...;

object[] args = new object [] { oMissing, oMissing, oMissing };
word.GetType().InvokeMember( "Quit", 
    BindingFlags.InvokeMethod | BindingFlags.Public | BindingFlags.Instance,
    null, word, args );

With the introduction of dynamics in C # 4, late binding is just a transition to a dynamic binder:

dynamic word = ...;

word.Quit();

, Quit. , intellisense.

, Dino:

http://msdn.microsoft.com/en-us/magazine/ff714583.aspx