ASP.NET MVC4 Model Binding

Question

Does anyone know when model binding takes place in the request lifecycle? The reason I ask is that I'm running into some localization issues.

Does Model Binding happen before OnActionExecuting is executed?

Currently I set the current culture in a global action filters OnActionExecuting method but this isn't being respected when performing model binding. The request is a POST.

Thanks in advance.

I had exact the same setup and question, thanks for asking ;) — Maarten Kieft, Jan 25 '13 at 13:33

score 3 · Answer 1 · answered Oct 09 '12 at 12:28

3

I would suggest you to set the culture at a very earlier point not in action filter. In my current project I've set the culture in the Application_AcquireRequestState event in Global.asax.cs. You can try that.

protected void Application_AcquireRequestState(Object sender, EventArgs e)
{
   // set the culture
}

answered Oct 09 '12 at 12:28

VJAI

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I guess that is indeed a better solution. – Maarten Kieft Jan 25 '13 at 13:33
This solution works for me but now it means this code runs for each request, not just for controller's actions. Any image or JS file that is been requested is now running this code which may impact performance. – Ido Ran Jul 15 '13 at 12:02

score 2 · Answer 2 · edited May 23 '17 at 12:30

I found that in a MVC application the best way is to use a custom routehandler and set the culture in that handler. This works flawlessly with ModelBinders and localized resources in data annotations.

public class MultiCultureMvcRouteHandler : MvcRouteHandler
{
    protected override IHttpHandler GetHttpHandler(RequestContext requestContext)
    {
        // get culture from route data
        var culture = requestContext.RouteData.Values["culture"].ToString();
        var ci = new CultureInfo(culture);
        Thread.CurrentThread.CurrentUICulture = ci;
        Thread.CurrentThread.CurrentCulture = CultureInfo.CreateSpecificCulture(ci.Name);
        return base.GetHttpHandler(requestContext);
    }
}

There is an excellent blog article by Alex Adamyan describing this technique.

See also this question & answers on SO.

score 0 · Accepted Answer · edited May 23 '17 at 12:30

BindModel is hit first. Can your localization change per request? If it does you could override the default model binder and if required set your locale there. Follow link below on creating custom model binder

ASP.NET MVC Model Binder for Generic Type

(to prove for yourself just put two breakpoints in and you'll see the order)

I'm thinking there might be a better place to set the localization but would need more specific information, and that might be a different question.

score 0 · Answer 4 · answered Jul 15 '13 at 13:19

I also run into the same problem. When the model binder has invalid data it runs before the ActionFilter(s).

I didn't like the proposed solutions because messing with the routing was not my preferred solution. Listen for Application_AcquireRequestState is problematic because this event fire for each and every request, not just for requests that will be routed into MVC controllers.

I've end up writing a custom implementation of IControllerFactory that use DefaultControllerFactory internally and execute the localization code inside CreateController method.
This is not ideal either, hope it helps.

  public class PluggableControllerFactory : IControllerFactory {

    private readonly IControllerFactory innerControllerFactory;

    public PluggableControllerFactory() {
      innerControllerFactory = new DefaultControllerFactory();
    }

    public IController CreateController(System.Web.Routing.RequestContext requestContext, string controllerName) {
      // Run your culture localization here

      return innerControllerFactory.CreateController(requestContext, controllerName);
    }

    public System.Web.SessionState.SessionStateBehavior GetControllerSessionBehavior(System.Web.Routing.RequestContext requestContext, string controllerName) {
      return innerControllerFactory.GetControllerSessionBehavior(requestContext, controllerName);
    }

    public void ReleaseController(IController controller) {
      innerControllerFactory.ReleaseController(controller);
    }

  }
}

ASP.NET MVC4 Model Binding

4 Answers4