Question

In a ASP.NET MVC (4) application, I am using a 3rd party Javascript library that auto-magically sends back a query string parameter with a poor name (IMO). I can intercept this value in model binding with the following:

public ActionResult MyAction([Bind(Prefix="rp")] int pageSize = 50) 
{
}

However, this code inside all the places where I use paging gets tiresome pretty quickly.

Is it possible inside ASP.NET MVC to globally set a [BindAttribute] with a specific prefix/replacement combination?

A workaround would be to modify the Javascript library (undesirable); or get the parameter out of the Request.QueryString property manually; but I was hoping to keep things cleaner.

Answer 1

You could use a view model:

public class MyViewModel
{
    public int PageSize { get; set; }
}

in your controller action(s):

public ActionResult MyAction(MyViewModel model) 
{
    ...
}

and then write a custom model binder for this view model:

public class MyViewModelBinder: DefaultModelBinder
{
    protected override void BindProperty(ControllerContext controllerContext, ModelBindingContext bindingContext, PropertyDescriptor propertyDescriptor)
    {
        bindingContext.ModelName = "rp";
        base.BindProperty(controllerContext, bindingContext, propertyDescriptor);
    }
}

that will be registered in Application_Start:

ModelBinders.Binders.Add(typeof(MyViewModel), new MyViewModelBinder());