如何使用DataContractJsonSerializer对字典进行反序列化?

I have the following model:

我有以下模型:

[DataContract]
public class MessageHeader
{
    private Guid? messageId;

    public Guid MessageId
    {
        get
        {
            if (messageId == null)
                messageId = Guid.NewGuid();

            return messageId.Value;
        }
    }

    [DataMember]
    public string ObjectName { get; set; }

    [DataMember]
    public Dictionary<string, object> Parameters { get; set; } // Can't deserialize this

    [DataMember]
    public Action Action { get; set; }

    [DataMember]
    public User InitiatingUser { get; set; }
}
[DataCo