Calling WCF Service with an out parameter

03-17-2008 9:01 AM |

Hi there,

How do i call a WCF web service which has an out parameter,

Example:

My service has the following signature

public List<Entity> ListAll(string languageID, out ResultObject resultObject) { }

When i consume this service in my SL application (code below), i only get to pass the languageID not the resultObject

EndpointAddress address = new EndpointAddress("http://localhost:5309/ContextManager/EntityService.svc");

proxy.ListAllCompleted += new EventHandler<ListViewDataGrid.ContextManager.EntityService.ListAllCompletedEventArgs>(proxy_ListAllCompleted);

proxy.ListAllAsync("en-US"); // it is not asking for the ResultObject parameter.

Re: Calling WCF Service with an out parameter

03-17-2008 11:19 AM |

The idea of an out parameter is that the method will instantiate the null reference that you pass in. A web service is stateless; therefore the handle that you have on an object that goes into a webservice as a parameter will not be the same as the one that makes it into the webservice server side. The nature of this prevents out parameters.

 Instead: Create a return object that is composed of everything you need.

 Stomp it!

Re: Re: Calling WCF Service with an out parameter

03-17-2008 1:01 PM |

Hey dude,

The web service is in production environment, so i cannot change it. Please tell me how to pass an out parameter from an SL application

thanx

Re: Re: Calling WCF Service with an out parameter

03-17-2008 1:56 PM |

Hey dude,

Oops, I wasn't aware that the proxy could handle such a thing as an out parameter. Pretty cool. Is there a reason that you are writing so much code to access the webservice. Didn't Visual Studio create a proxy class that you can instantiate and call methods on?

 StompIt!

Re: Re: Calling WCF Service with an out parameter

03-17-2008 2:21 PM |

This seems to be an odd situation, because looking at the References.cs for a webservice, the out parameter exists in the callbacks but not in the actual calls.

Re: Calling WCF Service with an out parameter

03-19-2008 3:18 AM |

Hi:

  If you use output parameters GetDataCompletedEventArgs will have relevant property for you to use. Say the parameter is called param1 you can retrieve it via:

  void proxy_GetDataCompleted(object sender, SilverlightApplication1.ServiceReference1.GetDataCompletedEventArgs e)
        {

//e.param1

        }

Regards

Re: Re: Calling WCF Service with an out parameter

03-19-2008 4:42 AM |

Hi there,

First of all the method in SL application doesn't even ask the out parameter.

Say i have a service method GetData(int id, out object test), when i add a service reference, the parameters asked are just the id but not the out parameter.

Re: Re: Calling WCF Service with an out parameter

11-27-2008 4:48 AM |

Hi,

How to pass ref paramer from silver light application to webservice.

I declared a method Test(string s ,ref string test)

How to call this method from silverlight

Thanks

Venkat 

Re: Re: Calling WCF Service with an out parameter

03-19-2009 7:10 AM |

Please check the result

} 

OMID is the "out" Parameter in my WCF Service.