Dynamic Objects in WCF not possible?

Question

When building a response in WCF (json), im pretty sure it\'s not possible to use completely dynamic objects, but just wanted to double check here first.

An ideal respons

Answer 1

Add the following using at the top of your service implementation class (make sure that you also add the proper references in your project):

using Newtonsoft.Json;
using System.Dynamic;
using System.IO;
using System.Text;

You may try this simple method which outputs the dynamic result:

public string GetData()
{
    dynamic d = new ExpandoObject();
    dynamic bartSimpson = new ExpandoObject();
    dynamic lisaSimpson = new ExpandoObject();
    bartSimpson.url = "foo";
    bartSimpson.desc = "bar";
    lisaSimpson.url = "foo";
    lisaSimpson.desc = "bar";
    d.userTypes = new ExpandoObject();
    d.userTypes.BartSimpson = bartSimpson;
    d.userTypes.LisaSimpson = lisaSimpson;
    var s = JsonSerializer.Create();
    var sb = new StringBuilder();
    using (var sw = new StringWriter(sb))
    {
        s.Serialize(sw, d);
    }
    return sb.ToString();
}

To go one more step further (you'll just have to pass Bart and Lisa in the comaSeparatedNames value), you could do:

public string GetData(string comaSeparatedNames)
{
    string[] names = comaSeparatedNames.Split(',');
    dynamic d = new ExpandoObject();
    dynamic dNames = new ExpandoObject();
    foreach (var name in names)
    {
        dynamic properties = new ExpandoObject();
        properties.url = "foo";
        properties.desc = "bar";
        ((IDictionary<string, object>)dNames).Add(name, properties);
    }
    ((IDictionary<string, object>)d).Add("userTypes", dNames);

    var s = JsonSerializer.Create();
    var sb = new StringBuilder();
    using (var sw = new StringWriter(sb))
    {
        s.Serialize(sw, d);
    }

    // deserializing sample
    //dynamic dummy = new ExpandoObject();
    //var instance = s.Deserialize(new StringReader(sb.ToString()), 
    //    dummy.GetType());
    //var foo = instance.userTypes.BartSimpson.url;

    return sb.ToString();
}

Note: I've also provided the lines (commented) for deserialization.