When I read books about WPF, I saw the authors mention XPS like it was something important. Windows also includes its XPS viewer, and I've seen that listed as a "feature" of Windows.
But why? What's the point? Who the heck uses it? It's my understanding that XPS is, basically, like PDF, xhtml, or ePub (which is just xhtml)...or even Word's docx format. Many of the features are the same among those formats.
It doesn't seem to have any major benefits compared to any of those other formats. It seems to me that xhtml would be so much more useful than XPS as a way to save and load FlowDocuments from the RichTextBox. I've looked at multiple blogs about converting between the two. Most or all of the rich text on the internet is (x)html. Beyond that, I don't think anyone uses it just to publish their docs; PDF is preferred. It seems like XPS is just some random format that MS made and decided to push. I generally love MS, but they do have a habit of that kind of thing. Couldn't MS have made an api using xhtml instead? That would have been more useful in a lot of situations, I'd think.
So, is there a point to using XPS, particularly in comparison to one of the other formats I mentioned (or any I haven't)? Have you ever used XPS in your programs or otherwise?
As U62 already stated, WPF comes with a DocumentViewer control which enables you to view XPS documents. The DocumentViewer also has some useful fonctions like Print, Zoom, FitToPage etc... So you don't need to implement that or use a third party tool.
What I just finished an hour ago using XPS and the DocumentViewer was some kind of "Adress label print preview". Allow the user to select some contacts from a list of contacts, click "Print Preview". This opens a new XAML Window which contains a DocumentViewer control and a ListBox with the choice of different Labels (e.g. 1 sheet with 12 labels [2 columns, 6 rows], 1 sheet with a single label whose width and height can be user defined). Based on the users selection, I generate an XPS Document in the layout the user selected with the adresses of the selected contacts. If e.g. the user selected 4 contacts and wishes to print them on "SingleLabelSheet"'s, I generate 1 XPS document with 4 pages, each page containing 1 Adress. Then I display the XPS in the DocumentViewer and the user can print the labels on our Label Printer.
Once I understood how the XPS API worked (at least the Basics), it was a matter of 2 hours to get this up and running.
So, basically, I see XPS as an easy to use API to display FixedDocuments which are to be generated on the fly. But I wouldn't personnally go about saving them to my HDD or somehow modify them or whatever you generally do with documents.