Hi Alan, as noted earlier a source control will notify if the modifications take place, including time, author etc stamp, however since in your case you want the modifications made for a class in A to be notified to B, you can work it different ways. firstly you can write a custom class that check for the change from the source control based on datatime stamp and sends a notification to a handler in B;
Another approach is that whenever class changes in site A, it creates an entry in a text..log file or a DB--a history table or file and the notifier program reads and compares the last value and notifies ..change.
Another approach is to use WCF or .net 3.0 to use a timer schedule that keeps monitoring a file and notifies each time the file is accessed or changed.
Hope that helps and I have understood your correctly
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