In this article I will explain with an example, how to convert Office Word document (Doc & Docx) files to HTML in ASP.Net MVC Razor.
The Office Word document i.e. Doc & Docx files will be first uploaded, then it will be converted to HTML using Microsoft Office Interop Library and finally it will be displayed in View in ASP.Net MVC Razor.
Adding reference of Microsoft Office Interop Library
In order to add reference of the Microsoft Office Interop Library, right click on the Project in Solution Explorer and click Add Reference.
Then from the following Window, please select Microsoft Office Interop.Word assembly.
Convert Word Document (Doc & Docx) to HTML in ASP.Net MVC
You will need to import the following namespaces.
using System.IO;
using Microsoft.Office.Interop.Word;
using System.Text.RegularExpressions;

The Controller consists of two Action methods.
Action method for handling GET operation
Inside this Action method, simply the View is returned.
Action method for handling POST operation
This Action method gets called when a Word Document file is selected and the Submit Button is clicked, and it gets the uploaded file in the HttpPostedFileBase parameter.
Note: In case the HttpPostedFileBase parameter is appearing NULL, then please refer the article, ASP.Net MVC: HttpPostedFileBase always returns NULL.
The uploaded Word Document file is first saved into a Folder named Temp within the Project Folder and then the Word Document file is converted into HTML string using Microsoft Office Interop Library.
Finally the HTML string will be assigned to a ViewBag object.
public class HomeController : Controller
    // GET: Home
    public ActionResult Index()
        return View();
    public ActionResult Index(HttpPostedFileBase postedFile)
        object documentFormat = 8;
        string randomName = DateTime.Now.Ticks.ToString();
        object htmlFilePath = Server.MapPath("~/Temp/") + randomName + ".htm";
        string directoryPath = Server.MapPath("~/Temp/") + randomName + "_files";
        object fileSavePath = Server.MapPath("~/Temp/") + Path.GetFileName(postedFile.FileName);
        //If Directory not present, create it.
        if (!Directory.Exists(Server.MapPath("~/Temp/")))
        //Upload the word document and save to Temp folder.
        //Open the word document in background.
        _Application applicationclass = new Application();
        applicationclass.Documents.Open(ref fileSavePath);
        applicationclass.Visible = false;
        Document document = applicationclass.ActiveDocument;
        //Save the word document as HTML file.
        document.SaveAs(ref htmlFilePath, ref documentFormat);
        //Close the word document.
        //Read the saved Html File.
        string wordHTML = System.IO.File.ReadAllText(htmlFilePath.ToString());
        //Loop and replace the Image Path.
        foreach (Match match in Regex.Matches(wordHTML, "<v:imagedata.+?src=[\"'](.+?)[\"'].*?>", RegexOptions.IgnoreCase))
            wordHTML = Regex.Replace(wordHTML, match.Groups[1].Value, "Temp/" + match.Groups[1].Value);
        //Delete the Uploaded Word File.
        ViewBag.WordHtml = wordHTML;
        return View();
Form for Uploading the Word Document file
This Form consists of an HTML FileUpload and a Submit Button. When the Button is clicked, the Index Action method for handling POST operation will be called.
Displaying the Word Document in View
The ViewBag object is displayed using the Html.Raw Helper function.
    Layout = null;
<!DOCTYPE html>
    <meta name="viewport" content="width=device-width"/>
    @using (Html.BeginForm("Index", "Home", FormMethod.Post, new { enctype = "multipart/form-data" }))
        <input type="file" name="postedFile"/>
        <input type="submit" value="submit"/>
Convert Word Document (Doc & Docx) to HTML in ASP.Net MVC