I'm able to generate Word documents without issue. I save the resulting *.docx file to a temporary location and then need to launch the file in Word.
The requirement is to not "open" the file in Word (easily done with a Process.Start) but to have load into Word as a new unsaved file. This is because certain propriety integrations for Word need to take over when a user saves the file and don't kick in if the file is ready saved but to a location on disk.
I've achieved this by using Interop calls to the Word application, adding the new document to Word's workspace. My problem is with Interop which tends to break on various client machines, particularly when Office upgrades take place (say a client had 32-bit office but upgraded with a 64-bit version).
I'm somewhat new to OpenXML, but can it be used to automate Word or is Interop my only real option?
object oFilename = tmpFileName;
object oNewTemplate = false;
object oDocumentType = 0;
object oVisible = true;
Document document = _application.Documents.Add(ref oFilename, ref oNewTemplate, ref oDocumentType, ref oVisible);
No, the Open XML technology has no way of interacting with the Office (Word) application - it's for file creation/manipulation, only. The interop is required in order to do anything with the Word application.
There is sort of a way around this - and it's only possible with Word, no other Office application has this - is to convert the Open XML content to the OPC flat-file format. This "concatenates" the various packages that make up the zip file to a pure text string, essetially a single XML file.
XML content in the OPC flat-file format can then be written to an already opened (even newly created) Word document using the Range.InsertXML method via "the interop". In a way, this "streams" the Open XML content into the opened Word document.
The problem with this approach is that certain document-level properties are not written to the target document, so not all aspects of the opened document can be changed. For example: page size, orientation, headers, footers... So if this kind of thing also needs to be affected the interop is required for such settings.