Multi-threaded web service client

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

chendricks - 02 Oct 2007 15:21 GMT

I have a C# winform client application that interacts with a library of web
services running on a single web site. The application makes multiple web
service calls in multiple background threads to avoid locking up the UI while
web service calls are processed. Some of these web service calls may be
concurrent.

Every now and then the client will lockup and becomes completely
unresponsive to the user. No exception is thrown. All the threads just stop.
I have already made sure that none of the background threads call a UI
control without using the Invoke method.

Is it safe to make multiple web service calls from multiple threads within a
single client application to a single web services server? Any suggestions on
what I'm doing wrong?

Thanks for any help,

Colin

Reply to this Message

Andrew Brook - 02 Oct 2007 15:28 GMT

Hi Colin,

Perhaps it would make the coding easier if you were to call the Async
versions of the web methods and pass in a callback function. At least that
way you wouldn't need to handle creating your own threads, and possibly
avoid further related troubles.

just a thought :)

Andrew

>I have a C# winform client application that interacts with a library of web
> services running on a single web site. The application makes multiple web
[quoted text clipped - 18 lines]
>
> Colin

Reply to this Message

chendricks - 02 Oct 2007 15:37 GMT

Yes, I've considered that and perhaps I'll try it. How are timeouts handled
under the async model in cases where the network is not available?

> Hi Colin,
>
[quoted text clipped - 29 lines]
> >
> > Colin

Reply to this Message

Andrew Brook - 02 Oct 2007 15:52 GMT

that's a good question - but i'm afraid I don't know the answer. You'd
expect an exception somewhere, but where it would surface I've got no idea.
I suppose it would be easy enough to test though.

Sorry!
Andrew

> Yes, I've considered that and perhaps I'll try it. How are timeouts
> handled
[quoted text clipped - 38 lines]
>> >
>> > Colin

Reply to this Message

Andrian - 07 Oct 2007 13:48 GMT

Colin,

When using asynchornous BeginMethod, any exception from that method will be
thrown when u call end EndMethod to complete the function call (if you
will). So the following code will give u an idea:

Proxy.BeginCall(new AsyncCallback(...));

void CallEnded(IAsyncResult state) // the callback function passed to the
BeginCall function
{
try
{
Proxy.EndCall(state);
}
}

the parameters or type of parameter passed to the functions may not be
compleely accurate, but its only an illustration.

Signature

Andrian

> that's a good question - but i'm afraid I don't know the answer. You'd
> expect an exception somewhere, but where it would surface I've got no
[quoted text clipped - 47 lines]
>>> >
>>> > Colin

Reply to this Message

Multi-threaded web service client

Free Magazines