Question

Ok, so I am using MVC 3 and it is great at de-serializing a JSON data set into a strongly typed object that is passed to my controller action. Unfortunately I have not found a solution to a more dynamic case.

Does the built in Json de-serialisation and classes have support for an “undefined” property set? For example lets say I have some fixed data like name and age, but I also want to pass down a dynamically created rating list where the user could enter (or select) a movie and set a rating value in a table.

The model data structure could be something like this:

public class UserRatings
{
  public string Name { get; set; }
  public int Age { get; set; }
  public Dictionary<string,int> Ratings { get; set; }
}

But assuming that my Json dataset looks like this from javascript:

var data = { Name: name, Age: age, Ratings: rating };

Where the rating variable is a dynamically constructed object that consist of the name (or id) of of the movie as key and rating as number. Naturally de-serialization of this in the controller action will not be successful as it does not understand the mapping of Ratings to the rather complex dictionary object. But is there a generic Json collection that I could use instead for Ratings as an intermediate format?

I have tried making the Ratings object a Json string in javascript and just sending a string down, but I am unable to find a “factory” or something that can make a Json structure in C# that I can iterate over to get the data out. The classes Json and JsonResult does not help me in this regard it seems. Basically how can I use the built in Json support in MVC to do my own de-serialisation into some generic Json collection object?

Answer 1

You Could Use JavaScriptSerializer or DataContractSerializer with Some ActionFilters. They’re very flexible