javascript event handler for custom user control

[ashish_gokhale]

Hi
I am developing a custom user control (an combobox emulation) by combinging
textbox and dropdownlist. I want to populate the textbox by value selected
in dropdownlist. There are many articles on internet which tell how to add
events in code behind files. However I want to handle this event in Javascript
to avoid post back. What is the syntax for this?

Thanks,
Ashish