Quick question, but is it best practice to wrap a service proxy class in a using statement? Meaning, in VS, we generated a proxy for a WCF service. For the service class, should it be wrapped in using? I don't believe it implements IDisposable and there is no Dispose() method. Thanks.
+3
A:
Although proxies generated by Service Reference and svcutil.exe do implement IDisposable, in general it is not a best practice to wrap them in a using block; instead favor explicit open and closing.
Why? Well, the problem is that the Dispose method calls Close, which can throw in various circumstances, most prominently if the channel is in a Faulted state. In general this is bad, but if this happens during a finally block because you let a fault exception bubble up, it could swallow the original fault exception in favor of the Close exception, effectively losing the original exception.
Randolpho
2010-09-21 15:22:10
Usually, I don't explicitly open and close. I usually initialize the service and invoke methods on it - never actually closing upon completion. I see this a lot too. Bad practice?
Ryan Peters
2010-09-21 15:26:52
@Ryan Peters: if you're using a `using` block, that wouldn't be bad practice, other than the issue I mentioned. But you should always close your channel when you're not using it, either explicitly or implicitly. Explicitly *opening* the channel, on the other hand, isn't always necessary, as the first operation call on the proxy will always open the channel.
Randolpho
2010-09-21 15:50:48
A:
Here is some reference for you, starting with an SO question:
Avoiding Problems with the Using Statement
The Problems with WCF and the Using Block
Avoiding Problems with the Using Statement and WCF Service Proxies
DOK
2010-09-21 15:35:19
A:
This is what we recommend people use - http://blogs.msdn.com/b/drnick/archive/2007/05/04/the-try-catch-abort-pattern.aspx
Sajay
2010-09-22 07:00:53