C# – Convert Word to HTML

During my development I need to convert Word to HTML. I have installed Word on my local machine and I believe there are already many available ways on Internet to convert Word to HTML. In this small example I would like to introduce a method without adding any reference to any COM Component. This method uses namespace System.Reflection to create an instance of word document and invoke functionality “Export to HTML” for converting. The following functions will be used
Type.GetTypeFromProgID Method: Gets the type associated with the specified program identifier (ProgID).
Activator.CreateInstance Method: Creates an instance of the specified type using the constructor that best matches the specified parameters.
Type.InvokeMember Method: When overridden in a derived class, invokes the specified member, using the specified binding constraints and matching the specified argument list, modifiers and culture.
And the complete source code of example is in following snippet

static void Main(string[] args)
        {
            ConvertWord2Html(@"E:\temp.doc", @"E:\temp.html");
            Console.WriteLine("Convert done");
            Console.ReadLine();
        }

        static void ConvertWord2Html(string strSource, string strDestination)
        {
            // Constant for WORD-TO-HTML exporting format
            const int WORD_HTML_FORMAT = 8;

            // Load COM-Metadata of Word application from registry
            Type tWordApplication = Type.GetTypeFromProgID("Word.Application");

            // Create new instance of Word
            object objWord = Activator.CreateInstance(tWordApplication);

            // List all documents
            object objDocuments = tWordApplication.InvokeMember("Documents", BindingFlags.IgnoreCase | BindingFlags.GetProperty | BindingFlags.Public, null, objWord, new object[0]);

            // Get COM-Metadata of Word Documents
            Type tWordDocuments = objDocuments.GetType();

            // Load source
            object objDocument = tWordDocuments.InvokeMember("Open", BindingFlags.IgnoreCase | BindingFlags.InvokeMethod | BindingFlags.Public | BindingFlags.OptionalParamBinding, null, objDocuments, new object[1] { strSource });

            // Get COM-Metadata of Word Documents
            Type tWordDocument = objDocument.GetType();

            // Create HTML 
            tWordDocument.InvokeMember("SaveAs", BindingFlags.IgnoreCase | BindingFlags.InvokeMethod | BindingFlags.Public | BindingFlags.OptionalParamBinding, null, objDocument, new object[2] { strDestination, WORD_HTML_FORMAT });

            // Close Word
            tWordApplication.InvokeMember("Quit", BindingFlags.IgnoreCase | BindingFlags.InvokeMethod | BindingFlags.Public | BindingFlags.OptionalParamBinding, null, objWord, new object[0]);
        }

Although this method is very comfortable, it doesn’t not allow us to monitor how long the converting still runs so that we can notify the user and allow him to cancel if it lasts too long, for example with very large Word document.