WPF: Display HTML-based content stored in resource assembly

Question

In my WPF project I need to render HTML-based content, where the content is stored in a resource assembly referenced by my WPF project.

I have looked at the WPF Frame and WebBrowser controls. Unfortunately, they both only expose Navigation events (Navigating, Navigated), but not any events that would allow me, based on the requested URL, to return HTML content retrieved from the resource assembly.

I can intercept navigation requests and serve up HTML content using the Navigating event and the NavigateToString() method. But that doesn't work for intercepting load calls for images, CSS files, etc.

Furthermore, I am aware of an HTML to Flowdocument SDK sample application that might be useful, but I would probably have to extend the sample considerably to deal with images and style sheets.

For what it is worth, we also generate the HTML content to be rendered (via Wiki pages) so the source HTML is somewhat predictable (e.g., maybe no JavaScript) in terms for referenced image locations and CSS style sheets used. We are looking to display random HTML content from the internet.

Update: There is also the possibility to create an MHT file for each HTML page, which would 'inline' all images as MIME-types and alleviate the need to have finer-grained callbacks.

Answer 1

If you're okay with using a 28 meg DLL, you may want to take a look at BerkeliumSharp, which is a managed wrapper around the awesome Berkelium library. Berkelium uses the chromium browser at its core to provide offscreen rendering and a delegated eventing model. There are tons of really cool things you can do with this, but for your particular problem, in Berkelium there is an interface called ProtocolHandler. The purpose of a protocol handler is to take in a URL and provide the HTTP headers and body back to the underlying rendering engine.

In the BerkeliumSharp test app (one of the projects available in the source), you can see one particular use of this is the FileProtocolHandler -- it handles all the file IO for the "file://" protocol using .NET managed classes (System.IO). You could do the same thing for a made up protocol like "resource://". There's really only one method you have to override called HandleRequest that looks like this:

bool HandleRequest (string url, ref byte[] responseBody, ref string[] responseHeaders)

So you'd take a URL like "resource://path/to/my/html" and do all the necessary Assembly.GetResourceStream etc. in that method. It should be pretty easy to take a look at how FileProtocolHandler is used to adapt your own.

Both berkelium and berkelium sharp are open source with a BSD license.

Answer 2

The WebBrowser exposes a NavigateToStream(Stream) method that might work for you:

If your content is then stored as an embedded resource, you could use:

var browser = new WebBrowser();
var source = Assembly.Load("ResourceAssemblyName");
browser.NavigateTo(source.GetManifestResourceStream("ResourceNamespace.ResourceName"));

There is also a NavigateToString(string) method that expects the string content of the document.

Note: I have never used this in anger, so I have no idea how much help it will be!