About WCF Clients

Windows Communication Foundation (WCF) is a runtime engine and set of APIs that allow you to send messages between clients and services using security settings and a communications protocol defined by service binding properties.

The WCF Client Proxy Project painter generates WCF client proxy objects that consume Web or WCF services from a PowerBuilder .NET application.

Note: You must install the Windows SDK for .NET Framework to use the WCF feature. The WCF Client Proxy project uses a tool from the SDK to access a service contract (svc or wsdl). This tool (SvcUtil.exe) parses the service contract and generates C# files. The C# compiler (CSC.exe from .NET Framework) then builds the newly generated C# code into a private assembly, which is automatically referenced by the project.

The nonvisual user object (NVO) proxy generated by the WCF Client Proxy project allows PowerBuilder .NET application users to consume a Web service or a WCF service. The proxy NVO represents the service class defined by the service contract, which is also incorporated in a private assembly generated by the WCF client project.

The proxy NVO can connect to services with bindings of type: basicHttpBinding, wsHttpBinding, netTcpBinding, and netNamedPipeBinding. If there are any other types of bindings specified in the service contract, the proxy NVO fails at compilation time.

The generated proxy layer uses PowerScript and .NET interoperability to pass the call to the assembly and get a return value from the service. This is different from the approach used by the Web service engine in PowerBuilder Classic, where the generated proxy uses the PowerBuilder Native Interface (PBNI) for data exchange. For this reason, you cannot migrate existing Web service clients from PowerBuilder Classic to the WCF engine.

The WCF client engine allows PowerBuilder .NET application users to consume WSE (Web Service Enhancement) extensions in addition to other Web services. The WSE extensions cannot be accessed by the EasySoap and .NET SOAP engines available in PowerBuilder Classic.