RTF TO HTML

Introduction

This is a simple trick for converting RTF to HTML.

Background 

All RTF are viewable in MS Word. Using Microsoft Word we can convert an RTF document to full HTML view. So after that we can extract the HTML source from the converted HTML file using a simple method. 

Using the code 

If you have MS Word, you can add the following code to do this task, just add Microsoft Word reference to your project.

//
// Add Microsoft.Office.Interop.Word
//  
using Word = Microsoft.Office.Interop.Word;    

public string ExtractHtml(string rtfText)
{
    try
    {
        //Create word object
        Word.Application applicationObject = new Word.Application();
        //define path for save your temporary file.
        string userTemp = Path.GetTempPath();
        //Open and save your rtf as HTML in your temp path.
        object missing = Type.Missing;
        object fileName = rtfText;
        object False = false;
        applicationObject.DisplayAlerts = Microsoft.Office.Interop.Word.WdAlertLevel.wdAlertsNone;

        Word.Document documentObject = 
           applicationObject.Documents.Open(ref fileName, ref missing, ref missing, ref missing,
                 ref missing, ref missing, ref missing, ref missing, ref missing,
                 ref missing, ref missing, ref False, ref missing, ref missing,
                  ref missing, ref missing);

        object tempFileName = Path.Combine(userTemp, "tempHtm.html");
        object fileFormt = Word.WdSaveFormat.wdFormatHTML;
        object makeFalse = false;
        object makeTrue = true;
        string absolutePath = tempFileName.ToString();
        if (File.Exists(absolutePath))
        {
            try
            {
                File.Delete(absolutePath);
            }
            catch { }
        }

        documentObject.SaveAs(ref tempFileName, ref fileFormt, 
           ref makeFalse, ref missing, ref makeFalse,
           ref missing, ref missing, ref missing, ref makeFalse, ref missing, ref missing,
           ref missing, ref missing, ref missing, ref missing, ref missing);
        GC.Collect();
        GC.WaitForPendingFinalizers();
        documentObject.Close(ref makeFalse, ref missing, ref missing);
        GC.Collect();
        GC.WaitForPendingFinalizers();
        File.Delete(rtfText);

        String htmlCode = "";

        //Extract html source from the temporary html file.
        if (File.Exists(absolutePath))
        {
            WebClient client = new WebClient();
            htmlCode = client.DownloadString(absolutePath);
            GC.Collect();
            GC.WaitForPendingFinalizers();
            try
            {
                File.Delete(absolutePath);
            }
            catch { }   
        }

        else
        {
            htmlCode = "";
        }
        
        return htmlCode;
    }
    catch
    {
        return "";
    }
}