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Recommended way to keep multiple event handlers?

 
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Hi,

Could anyone please recommend a design approach for keeping more than 1 event handler, for the same event ?
In particular, could you keep such handlers un-aware of each other?

Simplified example:
Say I started off with 2 independent requirements for a text input's "onkeyup()" :
- Some text-inputs should only allow lower-case letters
- Other(!) text-inputs should sound a 'beep' while tying.
Then this works:



However, later the requirements evolve, and *some* text-inputs need both effects (beep & lowercase). While other fields need a single effect (eg. just beep).
Of course, I could write a new 'onkeyup()' function that performs both actions (beep and lowercase).
But I really wish I could make it cleaner:


In real life my 'Handlers' are more complex, there are more Handlers and more combinations.
What is the best way to allow such combinations, while keeping my handlers un-aware of each other?

Thanks very much!

[ March 15, 2007: Message edited by: Sol Mam-Orn ]
[ March 15, 2007: Message edited by: Sol Mam-Orn ]
 
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Using DOM Level 0 Event handling, you are pretty much out of luck. At least not without a lot of mess.

Using the DOM Level 2 Event Model allows you to register multiple and independent handlers. The drawback is that it's browser dependent: there's the standard W3C way, and the Microsoft "we don't need no stinking standards" way.

Use of a library such as Prototype or jQuery eases the pain considerably.
 
Sol Mayer-Orn
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Thanks very much
 
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Take a look at this: http://www.pascarello.com/examples/testRegister.html

Eric
 
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