The ASP.NET MVC RC includes a number of file handling enhancements:

FileResult and File() helper method

The RC build adds a new FileResult class that is used to indicate that a file is being returned as an ActionResult from a Controller action method.  The Controller base class also now has a set of File() helper methods that make it easy to create and return a FileResult.

For example, let’s assume we are trying to build a photo management site.  We could define a simple “Photo” class like below that encapsulates the details about a stored Photo:

Figure 38

We could then use the new File() helper method like below to implement a “DisplayPhoto” action method on a PhotoManager controller that could be used to render the Photo out of a database store.  In the code below we are passing the File() helper the bytes to render, as well as the mime-type of the file. If we pointed a <img src=””/> element at our action method URL the browser would display the photo inline within a page:

Figure 39

If we wanted an end-user to be able to download the photo and save it locally, we could implement a “DownloadPhoto” action method like below.  In the code below we are passing a third parameter – which will cause ASP.NET MVC to set a header that causes the browser to display a “Save As…” dialog which is pre-populated with the filename we’ve supplied:

Figure 40

When a user clicks a link to the /PhotoManager/DowloadPhoto/1232 URL they’ll be prompted to save the picture:

Figure 41