How can I intercept the HTML from a ViewResult, modify it and serve it up?

Question

I'm writing a simple CMS.

I want to be able to load a View, having it included inside a master page, and then scan the HTML so that I can replace some custom tags (like {{blog}} with my own blog output) and then serve it up to the browser.

How can I get access to the HTML from the ViewResult in order to intercept it?

Answer 1

Sounds like you want to write an ActionFilterAttribute. This attribute has the following methods:

• OnActionExecuting - called just before the decorated action is executed
• OnActionExecuted - called after the action method is called, but before the ActionResult is rendered.
• OnResultExecuting - callled before the result is rendered
• OnResultExecuted - called after the result is rendered

There is an example here which returns either JSON or XML data depending on the "Content-type" header: Create REST API using ASP.NET MVC that speaks both Json and plain Xml

Answer 2

That's going to be tricky because the ViewResult writes its response directly to the Response.Stream. So you'll probably have to deal with the Response.Filter property to output the ViewResult to a MemoryStream so you can manipulate the content before returning a ContentResult. All this would happen in OnResultExecuting probably.