Does .NET 4 have a built-in JSON serializer/deserializer?

Solution 1:

You can use the DataContractJsonSerializer class anywhere you want, it is just a .net class and is not limited to WCF. More info on how to use it here and here.

Solution 2:

There's the JavaScriptSerializer class (although you will need to reference the System.Web.Extensions assembly the class works perfectly fine in WinForms/WPF applications). Also even if the DataContractJsonSerializer class was designed for WCF it works fine in client applications.

Solution 3:

Use this generic class in order to serialize / deserialize JSON. You can easy serialize complex data structure like this:

Dictionary<string, Tuple<int, int[], bool, string>>

to JSON string and then to save it in application setting or else

public class JsonSerializer
{
    public string Serialize<T>(T aObject) where T : new()
    {
        T serializedObj = new T();
        MemoryStream ms = new MemoryStream(); 
        DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(T));
        ser.WriteObject(ms, aObject);
        byte[] json = ms.ToArray();
        ms.Close();
        return Encoding.UTF8.GetString(json, 0, json.Length);
    }

    public T Deserialize<T>(string aJSON) where T : new()
    {
        T deserializedObj = new T();
        MemoryStream ms = new MemoryStream(Encoding.UTF8.GetBytes(aJSON));
        DataContractJsonSerializer ser = new DataContractJsonSerializer(aJSON.GetType());
        deserializedObj = (T)ser.ReadObject(ms);
        ms.Close();
        return deserializedObj;
    }
}