Is it possible to have a MVC controller with two actions of the same name with a parameter of T and List

Question

I'd like to have two methods on my controller with the same name but the only difference being the parameter one takes a parameter of T and the other of List

[HttpPost]
public ActionResult Edit(myType parameter)
{ 
    //snip
}

[HttpPost]
public ActionResult Edit(List<myType> parameter)
{ 
    //snip
}

The framework is throwing an exception so I am guessing this isn't possible.

The current request for action 'Edit' on controller type 'MyController' is ambiguous between the following action methods:

I'm calling these methods from a jQuery ajax call, where data could be T or an array of T.

$.ajax({
    url: url,
    type: "POST",
    contentType: "application/json, charset=utf-8",
    dataType: "json",
    data: JSON.stringify({ parameter: data }),
    success: function () {
        //success
    },
    error: function (e) {
        //error
    }
});

Note, similar, but different question here: http://stackoverflow.com/questions/436866/can-you-overload-controller-methods-in-asp-net-mvc — Nathan Koop, Jul 20 '12 at 15:45

score 0 · Answer 1 · answered Jul 20 '12 at 15:48

0

The key thing here is that you could surely just use overload that takes a List, and even if only passing a single object, you just end up with a list with 1 item in it. All you need to do is pass the data in as a json array.

answered Jul 20 '12 at 15:48

stevethethread

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Marcelo De Zen · Answer 2 · 2012-07-20T17:02:56.540

It seems that is not possible, the framework gets confused about what action you really want to call. But, can you simply maintain one of the actions above? Or each one do diferent things? If so, then your url scheme maybe needs a little revision.

If the two do more or less the same thing, you can add a parameter to specy if you want "mode 1" (single value) or "mode 2" (more values):

[HttpPost]
public ActionResult Edit(List<myType> parameter, bool? multiple)
{ 
    var multipleValues = multiple.GetValueOrDefault(true);
    if (!multipleValues)  ....
}

EDIT

You can use a custom ModelBinder to deserialize the json data.

Binder:

public class MyTypeBinder : IModelBinder
{
    public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
    {
        var request = controllerContext.HttpContext.Request;

        // reset input stream
        request.InputStream.Position = 0;

        // read content
        var jsonString = request.ContentEncoding.GetString(request.BinaryRead((int)request.InputStream.Length));

        var serializer = new JavaScriptSerializer();

        return jsonString.TrimStart().StartsWith("[")
            // array, just parse it
            ? serializer.Deserialize<List<MyType>>(jsonString)
            // single object, add to a list
            : new List<MyType>() { serializer.Deserialize<MyType>(jsonString) };
    }
}

Then, on the action:

public ActionResult Test([ModelBinder(typeof(MyTypeBinder))] List<MyType> type) 
{
   ....
}

Unfortunately this won't because the ajax call sends in either an array or a single object, if it's always an array this would be fine, but if it's a single object the parameter will be null. — Nathan Koop, Jul 20 '12 at 15:58

score 0 · Answer 3 · answered Jul 20 '12 at 15:48

0

Nathan,

you could try this:

[HttpPost, ActionName("Edit")]
public ActionResult EditMytype(myType parameter)
{ 
    //snip
}

[HttpPost]
public ActionResult Edit(List<myType> parameter)
{ 
    //snip
}

got something similar going in a project

answered Jul 20 '12 at 15:48

jim tollan

22,305
4
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This unfortunately throws the same exception as above. – Nathan Koop Jul 20 '12 at 15:57
dang, this certainly works in the scenario that i use it under. is the json.stringify def correct?? i.e. have you tried a test with a different controller action name to ensure that this is working? – jim tollan Jul 20 '12 at 15:59
I've tested where I comment out the one definition and then it works fine. – Nathan Koop Jul 20 '12 at 16:52

score 0 · Answer 4 · answered Jul 20 '12 at 16:08

[HttpPost, ActionName("EditType1")]
public ActionResult Edit(myType parameter)
{ 
    //snip
}

[HttpPost, ActionName("EditType2")]
public ActionResult Edit(List<myType> parameter)
{ 
    //snip
}

From the views,

/controllername/edittype1

/controllername/edittype2

Is it possible to have a MVC controller with two actions of the same name with a parameter of T and List

4 Answers4