Web service accepting an immutable object

Is it possible for a .NET web service to accept an immutable object (or an object containing referen开发者_运维百科ces to immutable objects) in a web method?

For example, if this is my web service method:

public class MyWebService : System.Web.Services.WebService
{
    [WebMethod]
    public void SetStatus(StatusData data)
    {
        // do something
    }
}

and StatusData contains an immutable property, Server will throw a System.Web.Services.Protocols.SoapException when method is called:

Unable to generate a temporary class (result=1).

Error CS0200: Property or indexer 'TestProject.Entities.StatusData.Id' cannot be assigned to -- it is read only

Can I still use immutable objects somehow, or is the only way to do it to map everything into mutable DTOs?

[Edit]

Obviously, I am not talking about strings, since string is a base type in .Net, and is really an exception to this problem. For example, XmlSerializer will not work (without explicit IXmlSerializable implementation) for any other immutable class.

But I was hoping that I could avoid manually writing a bunch of mutable DTOs (although the actual mapping can be automated).

Yes and this can be quickly demonstrated. Web services can accept strings which are immutable hence web services can accept immutable data.

What you're asking appears to be a slightly different question though. Can the web service serialization mechanism (XML serialization) handle an immutable object. Generally speaking no it cannot as XML serialization is based heavily on read/write properties which are not present on an immutable object.

Typically when I run into this situation I create 2 objects.

1. My normal immutable object for use in the majority of circumstances
2. A mutable version of my object which can easily be converted to and from the immutable version and is to be used in situations like serialization.

Well, it seems that there is no way but to use mutable DTOs for SOAP, so we used DTOs and AutoMapper to convert from immutable objects automatically.