I have a .Net DataAdapter\MetaDataAdapter serving a website, and have a requirement to cause a certain action on the clients' browser if a particular scenario occurs on the server.

For example, if I get particular information on the server that means my data source is unreliable, I need to inform the user (and possibly, through JS, cause some action on the client).

What is the best way of doing this? Perhaps calling the Failure method of the IItemEventListener? Or somehow using the Control.txt file (although I can't find any documentation on this)?