ASP MVC Replace View Generation With JSON At Run Time?

Question

Say I have a controller action like so:

public ActionResult Foo() {
    return View(new SomeModel {...});
}

Is it possible for me to, at runtime, have this action return JSON instead of HTML? This is for some automated testing. The only way I have found would be to modify my controller's base class to override View(...) such that they if some setting is true, it returns Json(model) instead of what it normally does.

I'd rather not do that as it would mean a conditional which gets evaluated for every action even in non-test environments.

You can try some like [Return either xml or json from MVC web api based on request](http://stackoverflow.com/q/13053485/580951). — Dustin Kingen, Feb 11 '15 at 18:33
@Nikolay, I only want to get JSON in a test environment -- so that won't work. — mamidon, Feb 11 '15 at 18:40
Executing an `if` statement is nothing compared to other operations performed in the method and rendering — Vsevolod Goloviznin, Feb 11 '15 at 18:42
Create `BaseController` with method `ViewOrJson` and in `ViewOrJson` check whether the `Microsoft.VisualStudio.TestTools.UnitTesting` is loaded in the current `AppDomain` — Nikolay Kostov, Feb 11 '15 at 18:44

score 0 · Answer 1 · answered Feb 11 '15 at 18:49

0

This is pretty trivial...

public ActionResult Foo() {
    var model = new SomeModel {...};

    if (somePropertyYouWantToCheck)
        return Json(model);

    return View(model);
}

answered Feb 11 '15 at 18:49

Erik Funkenbusch

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score 0 · Answer 2 · answered Feb 11 '15 at 18:53

0

I found the MVC feature which does exactly what I want -- filters. In my case, a global result filter which replaces the ActionResult with a JsonResult.

See http://weblogs.asp.net/gunnarpeipman/asp-net-mvc-3-global-action-filters

answered Feb 11 '15 at 18:53

mamidon

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Obviously I can edit the action itself to return JSON conditionally, but that's not scalable to our entire codebase -- hence global action filters. – mamidon Feb 13 '15 at 17:47
You do realize that action filters don't execute in unit testing, right? – Erik Funkenbusch Feb 13 '15 at 21:27

ASP MVC Replace View Generation With JSON At Run Time?

2 Answers2