C# coding std v1.81 / 38.a

[TT (Tom Tempelaere)]

Hi

I'm reading the C# coding standard and I don't understand the following item (38)

38. With delegates as class members
a) Copy a delegate to a local variable before publishing to avoid concurrency race condition

What is the reasoning here

Thanks
Tom

[Jon Skeet [C# MVP]]

TT (Tom Tempelaere) <"=?Utf-8?B?VFQgKFRvbSBUZW1wZWxhZXJlKQ==?=" <_N_
0SPA|/\|t*******@hotmail.com|/\|APS0_N_>> wrote:

I'm reading the C# coding standard and I don't understand the following item (38):

38. With delegates as class members:
a) Copy a delegate to a local variable before publishing to avoid
concurrency race condition.

What is the reasoning here?

You normally need to do a test for the delegate being null before
invoking it. If you don't copy it to a local variable first, you could
end up testing it for null, then trying to invoke it, with something
else setting it to null between the test and the invocation.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too

[TT (Tom Tempelaere)]

Thanks, Jon

Tom.