How do I prevent JSON serialization in ASP.NET MVC?

Question

While developing an ASP.NET MVC app, I'm finding a few places where my JsonResult actions throw an exception "A circular reference was detected while serializing an object".

For now, I'm removing the references in question, but ideally I'd like to simply mark the property such that the JSON serializer ignores it.

Can anyone suggest how I might do this?

Answer 1

[ScriptIgnore] should work (untested)

Answer 2

I've generally found that for complex objects its best to just serialize by creating a temporary 'inbetween' object :

For instance for testimonials I do the following. I actually do this in the codebehind for my ASPX model page.

This creates a nice JSON object. You'll notice I can even refactor my model and the page will still work. Its just another layer of abstraction between the data model and the page. I dont think my controller should know about JSON as much as possible, but the ASPX 'codebehind' certainly can.

    /// <summary>
    /// Get JSON for testimonials
    /// </summary>
    public string TestimonialsJSON
    {
        get
        {
            return Model.Testimonials.Select(
                x => new
                {
                    testimonial = x.TestimonialText,
                    name = x.name
                }
                ).ToJSON();
        }
    }

    In my ASPX I just do this in a <SCRIPT> block:
    var testimonials = <%= TestimonialsJSON %>;


    // oh and ToJSON() is an extension method
    public static class ObjectExtensions
    {
        public static string ToJSON(this Object obj)
        {
            return new JavaScriptSerializer().Serialize(obj);
        }
    }

I'm ready for the backlash against this suggestion... bring it on...

I'm not accessing data, merely reformatting a model for the View. This is 'view model' logic, not 'controller model' logic.

Answer 3

I would advise to use JSON.NET. It allows to serialize circular references and provides much more serialization options.

Answer 4

What Simon said. Add a little AutoMapper action to keep code weight under control.

Answer 5

I agree with Wyatt/Simon, MVVM all the way.