Serializing private member data

Question

I'm trying to serialize an object to XML that has a number of properties, some of which are readonly.

public Guid Id { get; private set; } 

I have marked the class [Serializable] and I have implemented the ISerializable interface.

Below is the code I'm using to serialize my object.

public void SaveMyObject(MyObject obj) {     XmlSerializer serializer = new XmlSerializer(typeof(MyObject));     TextWriter tw = new StreamWriter(_location);     serializer.Serialize(tw, obj);     tw.Close(); } 

Unfortunately it falls over on the first line with this message.

InvalidOperationException was unhandled: Unable to generate a temporary class (result=1). error CS0200: Property or indexer 'MyObject.Id' cannot be assigned to -- it is read only

If I set the Id property to public it works fine. Can someone tell me if I'm doing something, or at least if its even possible?

Answer 1

You could use DataContractSerializer (but note you can't use xml attributes - only xml elements):

using System; using System.Runtime.Serialization; using System.Xml; [DataContract] class MyObject {     public MyObject(Guid id) { this.id = id; }     [DataMember(Name="Id")]     private Guid id;     public Guid Id { get {return id;}} } static class Program {     static void Main() {         var ser = new DataContractSerializer(typeof(MyObject));         var obj = new MyObject(Guid.NewGuid());         using(XmlWriter xw = XmlWriter.Create(Console.Out)) {             ser.WriteObject(xw, obj);         }     } } 

Alternatively, you can implement IXmlSerializable and do everything yourself - but this works with XmlSerializer, at least.