可以使用可移植类库通过通道工厂在Silverlight中使用WCF服务吗？

Question

The Current Setup : Silverlight client consuming regular WCF services using RIA classes and generated service references.

The Goal : Replace the service references and RIA classes with channel factories and a Portable Class Library (PCL) . (XY goal: get rid of generated code.)

The Approach So Far :

The first part of this -- using channel factories -- is straightforward, and well documented. Basically, the WCF service remains as-is, with the caveat that the ServiceContract has to be defined on an interface. Then on the client you create a ChannelFactory<IMyService> , supply the service URL, and the proxy is created like magic (no need for a service reference).

There is a wrinkle with Silverlight, namely that you have to use conditional compilation to define asynchronous operation contracts. (This will be important in a moment when I try to move the operation contract to the PCL.) Thus the service contract will look something like this:

[ServiceContract]
public interface IMyService
{
#if SILVERLIGHT
    [OperationContract(AsyncPattern = true)]
    IAsyncResult BeginGetAString(AsyncCallback callback, object state);
    string EndGetAString(IAsyncResult result);
#else
    [OperationContract]
    string GetAString();
#endif
}

Note that it is (apparently) necessary to exclude the synchronous operation from the Silverlight compilation, as above. Otherwise, the call to ChannelFactory.CreateChannel complains:

The contract 'IMyService' contains synchronous operations, which are not supported in Silverlight. Split the operations into "Begin" and "End" parts and set the AsyncPattern property on the OperationContractAttribute to 'true'. Note that you do not have to make the same change on the server.

So far so good. The next step is to move code that is shared between client and server, from RIA .shared class files to a PCL. For the DataContract classes, this works perfectly well -- but trying to move the OperationContract class presents a problem. The Silverlight ChannelFactory approach requires the conditional compilation of the synchronous method definition, as above, which (as is my understanding) is not possible in a PCL.

The Question :

What is the most straightforward way (if any) to get this to work, short of abandoning the channel factory approach or maintaining an RIA project? For example, is there any way to tell Silverlight to simply ignore synchronous operations, rather than throwing an error? Or any way to somehow exclude the synchronous definition for the Silverlight-targeted PCL (eg, a conditional build maybe)?

Answer 1

Have you seen this post . This article will show you how to consume plain WCF services in Silverlight without the need to statically generate code for a service proxy (aka VS Add Service Reference wizard)