Hi Leo,

If you want to have only one caller at a time, you could create a singleton
that keeps track of how many callers are in call, and have any web method
then increment the count (lock here) check that count, and if it is > 1
with the lock still active, decrement, unlock and then throw an exception.

It is most unusual to expose this kind of requirement via web service, at
least this is the first request of this nature I've seen.  The reason is
that if there are multiple callers, there is no way to gate who calls when,
so I'd expect the client satisfaction to be pretty low on this approach.  
Why do you want to impose this kind of limit?

I hope this helps

Dan Rogers
Microsoft Corporation
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Thread-Topic: prevent concurrent access to my web service
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Subject: prevent concurrent access to my web service
Date: Tue, 7 Dec 2004 03:51:03 -0800
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How do I prevent concurrent access to my web service. How to avoid it.