I have a design problem and hopefully the braintrust which is stack exchange can help. I have a generic form, which loads a dataset and displays it. It never has direct knowledge of what it contains but can pass it to a service for manipulation (via an Onclick event for example). However, the form might need to alter its behaviour based on the manipulation by the service. Example: The service realises this dataset requires sending of an email by the user and needs to send an instruction to the form to open up a mail form. My idea is thus: I'm thinking about passing back some type of key/name dictionary, filled with commands which the service requires. They could then be interpeted by the form without it need to reference something specific. Example: IF the service decides that the dataset needs to refresh it would send back a key/name pair, I might even be able to chain commands. Refreshing the dataset and sending a mail. Refresh / "Foo" Mail / "[email protected]" The form would reference an action explicitly (Refresh or Mail) but not the instructions themselves. Is this a valid idea or am I wasting time?