Do I need to close a .NET service reference client when I'm done using it

I'm trying to find out if it is neccessary to close a .net service reference client when you are done using it. Almost all of the examples that I have come across on the net don't seem to, but the client that is generated implements IDisposable and since it does open a connection to a service, my intuition tells me you need to close that connection when you are done with it.

Here is a code sample I pulled from :

private void button1_Click(System.Object sender, System.EventArgs e)
    ServiceReference1.Service1Client client = new 
    string returnString;

    returnString = client.GetData(textBox1.Text);
    label1.Text = returnString;

I would think that you should at least call client.Close() at the end of this method, and better yet wrap the first line in a using statement. I just wanted to get some feedback on this to find out what the best practices are.


Yes, you do, but you need to be very careful when doing so. While closing anything that implements ICommunicationObject the potential exists to cause the disposal of the object to take an excessive amount of time in the event that there is an error or fault on the channel.

Because of this, it is prescribed that you call the Close method and then call the Dispose method on IDisposable, using a number of catches for certain exception types and calling Abort before you finally call Dispose.

You can wrap this logic up in an IDisposable implementation which you can use in a using statement.

The key here is to create a token that implements IDisposable and then in that implementation, call Close, catch the relevant exceptions, call Abort (if necessary) and then call Dispose.

This is implemented as an extension method which returns an IDisposable on it which in turn allows you to use it in a using statement.

Best practice is, if the class implements IDisposable, call Dispose() in a finally clause, or wrap it with using () { }

Edit Following the @casperOne comment below, it seems WCF clients should be treated more cautiously. I didn't know that, and am a little unsettled by it, with using() having served me well thus far.

The best thing to do is look at the generated client code for Dispose() and see if it's really disposing of anything, like HTTP connections or something.

On one hand, it may just be that the interface it implements inherits from IDisposable because some client might need to dispose of something, even though that particular one doesn't. That's similar to MemoryStream, a class that implements IDisposable because all Streams do, but that doesn't actually deal with any unmanaged resources.

On the other hand, it never hurts to use using, even if Dispose() is an empty method. And MS examples are actually really bad about not using using even if they should (e.g. here), so don't take their example as good evidence that you don't need to.

Need Your Help

Navigation bar has wrong position when modal a view controller with flip horizontal transition in iOS 7

cocoa-touch ios7 uinavigationbar

When I am trying to modal a view controller with flip horizontal transition in iOS7, the origin of navigation bar is (0, 0) at beginning and then jump to the right position at (0, 20). Is it possib...

Curl and wget: why isn't the GET parameter used?

shell curl wget

I am trying to fetch data from this page using wget and curl in PHP. As you can see by using your browser, the default result is 20 items but by setting the GET parameter iip to number x, I can fet...