How can I add a custom root node when serializing an object with JSON.NET?

Espo picture Espo · Dec 12, 2012 · Viewed 25k times · Source

I have added a custom property to some of my objects like this:

[JsonCustomRoot("status")]
public class StatusDTO 
{
    public int StatusId { get; set; }
    public string Name { get; set; }
    public DateTime Created { get; set; }
}

The attribute is very simple:

public class JsonCustomRoot :Attribute
{
    public string rootName { get; set; }

    public JsonCustomRoot(string rootName)
    {
        this.rootName = rootName;
    }
}

The default output from JSON.NET when serializing an instance of an object is this:

{"StatusId":70,"Name":"Closed","Created":"2012-12-12T11:50:56.6207193Z"}

Now the question is: How can I add a root-node to the JSON with the value of the custom attribute like so:

{status:{"StatusId":70,"Name":"Closed","Created":"2012-12-12T11:50:56.6207193Z"}}

I have found several articles mentioning the IContractResolver interface, but I cannot grasp how to do it. My attempts include this unfinished piece of code:

protected override JsonObjectContract CreateObjectContract(Type objectType)
{
    JsonObjectContract contract = base.CreateObjectContract(objectType);

    var info = objectType.GetCustomAttributes()
                   .SingleOrDefault(t => (Type)t.TypeId==typeof(JsonCustomRoot));
    if (info != null)
    {
        var myAttribute = (JsonCustomRoot)info;
        // How can i add myAttribute.rootName to the root from here?
        // Maybe some other method should be overrided instead?
    }

    return contract;
}

Answer

BuddhiP picture BuddhiP · Dec 12, 2012

What if you use an anonymous object?

JSON.Serialize(new { status = targetObject});