Streaming In Memory Word Document using OpenXML SDK w/ASP.NET results in "corrupt" document

Question

I am unable to stream a word document that I create on the fly down to the browser. I am constantly getting a message from Microsoft Word that the document is corrupt.

When I run the code via a Console Application and take ASP.NET out of the picture, the document is generated correctly with no problems. I believe everything centers around writing the file down.

Here is my code:

using (MemoryStream mem = new MemoryStream())
{
    // Create Document
    using (WordprocessingDocument wordDocument = WordprocessingDocument.Create(mem, WordprocessingDocumentType.Document, true))
    {
        // Add a main document part. 
        MainDocumentPart mainPart = wordDocument.AddMainDocumentPart();

        new Document(new Body()).Save(mainPart);

        Body body = mainPart.Document.Body;
        body.Append(new Paragraph(new Run(new Text("Hello World!"))));

        mainPart.Document.Save();
        // Stream it down to the browser

        // THIS IS PROBABLY THE CRUX OF THE MATTER <---
        Response.AppendHeader("Content-Disposition", "attachment;filename=HelloWorld.docx");
        Response.ContentType = "application/vnd.ms-word.document";
        mem.WriteTo(Response.OutputStream);
        Response.End();
    }
}

I have looked at a lot of links – but nothing quite works. I lot of people use MemoryStream.WriteTo and some use BinaryWrite – at this point I'm not sure what the correct way is. Also I've tried the longer content type, i.e. application/vnd.openxmlformats-officedocument.wordprocessingml.document but no luck.

Some screenshots – even if you try to recover you get the same "parts are missing or invalid"

Solution for those who stumble on this question:

Within the using directive of the WordProcessingDocument, you must call:

wordDocument.Save();

Also to correctly stream the MemoryStream, use this in the outer using block:

Response.ContentType = "application/vnd.openxmlformats-officedocument.wordprocessingml.document";
Response.AppendHeader("Content-Disposition", "attachment;filename=HelloWorld.docx");
mem.Position = 0;
mem.CopyTo(Response.OutputStream);
Response.Flush();
Response.End();

Wifeless

How do you add a wordDocument.Save(); ? I tried and the only possible code close to it is .Close() and that doesnt work for me. – Shibboleth

Answer 1

Use CopyTo instead, there is a bug in WriteTo which makes it fail to write the entire content of the buffer when the target stream does not support writing everything in one go.

Dempsey

Answer 2

As variant for .NET Framework 3.5 and lower. This version of framework haven't method CopyTo in class Stream. Therefore, method WriteTo is replaced by next code:

byte[] arr = documentStream.ToArray();
fileStream.Write(arr, 0, arr.Length);

Example was found by http://blogs.msdn.com/b/mcsuksoldev/archive/2010/04/09/creating-a-new-microsoft-word-document-from-a-template-using-openxml.aspx

Incus

Answer 3

I believe your ContentType value is incorrect; that is for Word 97 - 2003 format. Change it to:

application/vnd.openxmlformats-officedocument.wordprocessingml.document

and see if that fixes the problem.

Giulio

Answer 4

I copied and pasted your code and noticed that the :"wordDocument.close();" clausule was missing, added it and it worked (I did it in Asp.NET MVC witing an action)

Soubriquet

Answer 5

(This is using OpenXML SDK v 2.10.0 and .Net Core v2.2)

I know this has been answered but I wanted to throw out another option. It is correct that trying to send a stream back in File() like below will result in a corrupt document:

                MemoryStream updateStream = new MemoryStream();
                wordDocument.Save();
                wordDocument.Clone(updateStream);


                return File(updateStream, "application/vnd.openxmlformats-officedocument.wordprocessingml.document");

`

A super simple alternative/workaround would be to simply convert your stream to a byte[] like below and it will result in a working word docx

                MemoryStream updateStream = new MemoryStream();
                wordDocument.Save();
                wordDocument.Clone(updateStream);


                return File(updateStream.ToArray(), "application/vnd.openxmlformats-officedocument.wordprocessingml.document");

Crowbar

Answer 6

To expand on Rodion's answer and match the variables used in the questions this is what worked for me:

Response.ContentType = "application/vnd.openxmlformats-officedocument.wordprocessingml.document";
Response.AppendHeader("Content-Disposition", "attachment;filename=HelloWorld.docx");
mem.Position = 0;
byte[] arr = mem.ToArray();
Response.BinaryWrite(arr);
Response.Flush();
Response.End();

Mown

Answer 7

First of all, always include Content-Length. If browser does not know the length of the http response body, then the connection remains opened (keep-alive). If there is no other way, save content to temp file (with delete on close option), and then get the content length.

Second, the document processing IN-MEM does not work for all options (for example, you cannot insert chunk into the document. You must use file mode).

Below is the sample for aspnet core :

[HttpPost]
public async Task<ActionResult<MopedResponse>> PostAsync(IFormCollection collection)
{

    string pathTemp = Path.GetTempFileName(); // get the temp file name

    // create or process the word file

    // reopen it for serving

    FileStream merged = new FileStream(pathTemp, FileMode.Open, FileAccess.Read, FileShare.None, 4096, FileOptions.DeleteOnClose);

    System.Net.Mime.ContentDisposition cd = new System.Net.Mime.ContentDisposition
    {
        FileName = "parafa.docx",
        Inline = true  // false = prompt the user for downloading;  true = browser to try to show the file inline
    };
    Response.Headers.Add("Content-Disposition", cd.ToString());
    Response.Headers.Add("Content-Length", merged.Length.ToString());

    return File(merged, "application/vnd.openxmlformats-officedocument.wordprocessingml.document", "mywordFile1.docx");

}

Jesselton