Json – ASP.NET MVC controller actions that return JSON or partial html


I am trying to create controller actions which will return either JSON or partial html depending upon a parameter. What is the best way to get the result returned to an MVC page asynchronously?

Best Solution

In your action method, return Json(object) to return JSON to your page.

public ActionResult SomeActionMethod() {
  return Json(new {foo="bar", baz="Blech"});

Then just call the action method using Ajax. You could use one of the helper methods from the ViewPage such as

<%= Ajax.ActionLink("SomeActionMethod", new AjaxOptions {OnSuccess="somemethod"}) %>

SomeMethod would be a javascript method that then evaluates the Json object returned.

If you want to return a plain string, you can just use the ContentResult:

public ActionResult SomeActionMethod() {
    return Content("hello world!");

ContentResult by default returns a text/plain as its contentType.
This is overloadable so you can also do:

return Content("<xml>This is poorly formatted xml.</xml>", "text/xml");