Convert open xml string to byte[]

Question

so, I am editing a word document, using OpenXML. And for some reasons, I convert it all into a string :

//conversion du byte en memorystream
using (var file = new MemoryStream(text))
using (var reader = new StreamReader(file))
{
    WordprocessingDocument wordDoc = WordprocessingDocument.Open(file, true);
    using (StreamReader sr = new StreamReader(wordDoc.MainDocumentPart.GetStream()))
    {
        docText = sr.ReadToEnd();
    }
}

And then, I convert it as a byte.

But, a simple convert will not work:

byte[] back2Byte = System.Text.Encoding.ASCII.GetBytes(docText );

Because the string is a open xml string.

Tried this, but always got a corrupted file when I tried to open it with Word:

var repo = new System.IO.MemoryStream(System.Text.Encoding.UTF8.GetBytes(docText));

byte[] buffer = new byte[16 * 1024];
MemoryStream ms = new MemoryStream();

int read;
while ((read = repo.Read(buffer, 0, buffer.Length)) > 0)
{
    ms.Write(buffer, 0, read);
}

byte[] back2Byte = ms.ToArray();

So, this doesn't work either:

byte[] back2Byte = new byte[docText.Length * sizeof(char)];
System.Buffer.BlockCopy(docText.ToCharArray(), 0, back2Byte, 0, back2Byte.Length);

edit : After some checkings, it seems it is write as a openxml document into the database, and so, word cannot read it. There is no error when i open it with notepad

How can I correct this?

So, the real issue is, how can I convert a OpenXML string to a byte that can be open in word?

Answer 1

You cannot do this sort of thing. You are getting the bytes for only one part of an OpenXML document. By definition, all Microsoft Office documents are multi-part OpenXML documents. You could theoretically capture the bytes for all the parts using a technique like you're currently using, but you would also have to capture all the part/relationship information necessary to reconstruct the multi-part document. You'd be better off just reading all the bytes of the file and storing them as-is:

// to read the file as bytes
var fileName = @"C:\path\to\the\file.xlsx";
var fileBytes = File.ReadAllBytes(fileName);

// to recreate the file from the bytes
File.WriteAllBytes(fileName, fileBytes)

If you need a string form of those bytes, try this:

// to convert bytes to a (non-readable) text form
var fileContent = Convert.ToBase64String(fileBytes);

// to convert base-64 back to bytes
var fileBytes = Convert.FromBase64String(fileContent);

Either way, there is absolutely no need to use the OpenXML SDK for your use case.