WCF DataContract with readonly properties

Question

Hi,

I'm trying to return a complex type from a service method in WCF. I'm using C# and .NET 4. This complex type is meant to be invariant (the same way .net strings are). Furthermore, the service only returns it and never recieves it as an argument.

If I try to define only getters on properties I get a run time error. I guess this is because no setters causes serialization to fail. Still, I think this type should be invariant.

Example:

[DataContract]
class A 
{
   [DataMember]
   int ReadOnlyProperty {get; private set;}
}

The service fails to load due to a problem with serialization.

Is there a way to make readonly properties on a WCF DataContract? Perhaps by replacing the serializer? If so, how? If not, what would you suggest for this problem?

Thanks,
Asaf

Answer 1

Have you tried making the setter private?

Something like:

public string MyProperty
{
get;
private set;
}

Answer 2

put [DataMember] on backing field, you won't need a setter.

Answer 3

DataMember Field can't be readonly, because wcf dont serialize object as-is and every time befor deserialization starts creates new object instance, using default constructor. Dispatchers use setters to set field values after deserialization.

But all upper text can be a big mistake :)

To make them realy readonly, make the server logic, validating thiss field values.