R – attribute for .net MVC controller action method

asp.net-mvcauthenticationmembership-providerroleprovider

Essentially I want to show a friendly message when someone is not part of a role listed in my attribute. Currently my application just spits the user back to the log in screen. I've read a few posts that talk about creating a custom attribute that just extends [AuthorizeAttribute], but I'm thinking there's got to be something out of the box to do this?

can someone please point me in the right direction of where I need to look to not have it send the user to the log in form, but rather just shoot them a "not authorized" message?

Best Answer

If simplicity or total control of the logic is what you want you can call this in your action method:

User.IsInRole("NameOfRole");

It returns a bool and you can do the rest of your logic depending on that result.

Another one that I've used in some cases is:

System.Web.Security.Roles.GetRolesForUser();

I think that returns a string[] but don't quote me on that.

EDIT: An example always helps...

public ActionResult AddUser()
{
    if(User.IsInRoles("SuperUser")
    {
        return View("AddUser");
    }
    else
    {
        return View("SorryWrongRole");
    }
}

As long as your return type is "ActionResult" you could return any of the accepted return types (ViewResult, PartialViewResult, RedirectResult, JsonResult...)

Related Solutions

Asp.net-mvc – Can an ASP.NET MVC controller return an Image

Use the base controllers File method.

public ActionResult Image(string id)
{
    var dir = Server.MapPath("/Images");
    var path = Path.Combine(dir, id + ".jpg"); //validate the path for security or use other means to generate the path.
    return base.File(path, "image/jpeg");
}

As a note, this seems to be fairly efficient. I did a test where I requested the image through the controller (http://localhost/MyController/Image/MyImage) and through the direct URL (http://localhost/Images/MyImage.jpg) and the results were:

MVC: 7.6 milliseconds per photo
Direct: 6.7 milliseconds per photo

Note: this is the average time of a request. The average was calculated by making thousands of requests on the local machine, so the totals should not include network latency or bandwidth issues.

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

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");

Best Answer

Related Solutions

Asp.net-mvc – Can an ASP.NET MVC controller return an Image

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

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