MVC.NET C#: getting the emitted empty null values of a JSON httpPost?
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I have a WebService, that expects a list of a defined type via Json.

Class:


    public class myType
    {
        public int id { get; set;}
        public int? varA { get; set;}
        public string varB { get; set;}
        public float? varC { get; set;}
    }
Logic:

    //Passed JSON --> Data:{'id':'1','valueA':''}
    [HttpPost]
    public JsonResult Update(List<myType> Data)
    {
        //Data ends up with value's id = 1; varA = null; varB = null; varC = null;
        //So how can I find that valueA was actually passed with a null value, and all the 
        //others are just nulling by default?
        if (myType.varA.HasValue) dbItem.varA = myType.varA
        ...
    }

Lets assume myType has several values, eg {id, varA, varB, varC}
all values except id are nullable.

Now, I purposely want to null out only 1 value

the problem is, For bandwidth conservation, I'm only sending the id, and whatever value has been updated in JSON eg: `Data:{'id':'1','valueA':''}`, as far as the method is consurned though, the Data Object, returns the object that gives the `id`, but also gives a null value for all other variables of the object.

So, what can I to to be able to tell which emited variables were sent via the json to the webmethod? So I can tell which variable I was really wanting to null?