WCF custom serializer do not work

问题:

Want to replace wcf serializer with a custom one. After googling I've found examples. But it do not work. Here is my code: Substitutor:

    internal class MySerializerSubstitutor : DataContractSerializerOperationBehavior
    {
        private static readonly MySerializer _serializer = new MySerializer();
        public MySerializerSubstitutor (OperationDescription operationDescription)
            : base(operationDescription)
        {

        }

        public override XmlObjectSerializer CreateSerializer(Type type, string name, string ns, IList<Type> knownTypes)
        {
            return _serializer; //NEVER CALLED
        }

        public override XmlObjectSerializer CreateSerializer(Type type, XmlDictionaryString name, XmlDictionaryString ns, IList<Type> knownTypes)
        {
            return _serializer; // NEVER CALLED
        }
    }

Behavior which repolace serializer

public class MySerializerBehavior : IOperationBehavior
{

.......

public void ApplyDispatchBehavior(OperationDescription description, DispatchOperation dispatch)
    {
        var dcs = description.Behaviors.Find<DataContractSerializerOperationBehavior>();

        if (dcs != null)
            description.Behaviors.Remove(dcs);

        description.Behaviors.Add(new MySerializerSubstitutor(description)); //works fine
    }

.............

}

And host:

protected override void ApplyConfiguration()
{
var behavior = new MySerializerBehavior()
                foreach (var op in Description.Endpoints.SelectMany(ep => ep.Contract.Operations))
                {
                    op.Behaviors.Add(behavior);
                }
}

Whats wrong with this code?

回答1:

One problem that is immediately visible is that you cannot replace a behavior from a behavior. According to MSDN:

All of the IOperationBehavior methods pass an OperationDescription object as a parameter. This parameter is for examination only; if you modify the OperationDescription object the execution behavior is undefined.

http://msdn.microsoft.com/en-us/library/system.servicemodel.description.ioperationbehavior.aspx

I am not 100% sure what you are trying to accomplish, but here is an example that modifies properties of the serializer behavior.

http://msdn.microsoft.com/en-us/library/system.servicemodel.description.datacontractserializeroperationbehavior.aspx

If you need more customization than the properties provide you can try to replace the DataContractSerializerOperationBehavior. EDIT: Just make sure you add it before calling Open. See this article for adding a new behavior http://msdn.microsoft.com/en-us/library/ms730137.aspx