ContactController5.cs

// Map parameters on method to data from JSON
var parameterList = new List<object>();
foreach (var parameterInfo in methodInfo.GetParameters())
{
    var helpObj = Activator.CreateInstance(parameterInfo.ParameterType);
    help.Add(helpObj);

    var pJson = parameters[parameterInfo.Name] as JObject;
    var pObj = pJson.ToObject(parameterInfo.ParameterType);
    parameterList.Add(pObj);
}