What is the difference between ViewResult()
and ActionResult()
in ASP.NET MVC?
public ViewResult Index()
{
return View();
}
pu
While other answers have noted the differences correctly, note that if you are in fact returning a ViewResult only it is better to return the more specific type rather than the base ActionResult type. An obvious exception to this principle is when your method returns multiple types deriving from ActionResult.
For a full discussion of the reasons behind this principle please see the related discussion here: Must ASP.NET MVC Controller Methods Return ActionResult?
ActionResult is an abstract class that can have several subtypes.
ViewResult - Renders a specifed view to the response stream
PartialViewResult - Renders a specifed partial view to the response stream
EmptyResult - An empty response is returned
RedirectResult - Performs an HTTP redirection to a specifed URL
RedirectToRouteResult - Performs an HTTP redirection to a URL that is determined by the routing engine, based on given route data
JsonResult - Serializes a given ViewData object to JSON format
JavaScriptResult - Returns a piece of JavaScript code that can be executed on the client
ContentResult - Writes content to the response stream without requiring a view
FileContentResult - Returns a file to the client
FileStreamResult - Returns a file to the client, which is provided by a Stream
FilePathResult - Returns a file to the client
In Controller i have specified the below code with ActionResult which is a base class that can have 11 subtypes in MVC like: ViewResult, PartialViewResult, EmptyResult, RedirectResult, RedirectToRouteResult, JsonResult, JavaScriptResult, ContentResult, FileContentResult, FileStreamResult, FilePathResult.
public ActionResult Index()
{
if (HttpContext.Session["LoggedInUser"] == null)
{
return RedirectToAction("Login", "Home");
}
else
{
return View(); // returns ViewResult
}
}
//More Examples
[HttpPost]
public ActionResult Index(string Name)
{
ViewBag.Message = "Hello";
return Redirect("Account/Login"); //returns RedirectResult
}
[HttpPost]
public ActionResult Index(string Name)
{
return RedirectToRoute("RouteName"); // returns RedirectToRouteResult
}
Likewise we can return all these 11 subtypes by using ActionResult() without specifying every subtype method explicitly. ActionResult is the best thing if you are returning different types of views.
ActionResult is an abstract class.
ViewResult derives from ActionResult. Other derived classes include JsonResult and PartialViewResult.
You declare it this way so you can take advantage of polymorphism and return different types in the same method.
e.g:
public ActionResult Foo()
{
if (someCondition)
return View(); // returns ViewResult
else
return Json(); // returns JsonResult
}
To save you some time here is the answer from a link in a previous answer at https://forums.asp.net/t/1448398.aspx
ActionResult is an abstract class, and it's base class for ViewResult class.
In MVC framework, it uses ActionResult class to reference the object your action method returns. And invokes ExecuteResult method on it.
And ViewResult is an implementation for this abstract class. It will try to find a view page (usually aspx page) in some predefined paths(/views/controllername/, /views/shared/, etc) by the given view name.
It's usually a good practice to have your method return a more specific class. So if you are sure that your action method will return some view page, you can use ViewResult. But if your action method may have different behavior, like either render a view or perform a redirection. You can use the more general base class ActionResult as the return type.
It's for the same reason you don't write every method of every class to return "object". You should be as specific as you can. This is especially valuable if you're planning to write unit tests. No more testing return types and/or casting the result.