Textbox Value Change Event

[elicaf]

Is it possible to update one textbox when a value is entered in another textbox?
Like in Visual Basic on the Change event - if you have a quantity and total textbox, when someone enters a quantity the totals textbox will show the price without having to submit the form. Or even to be able to display on the form the totals?

[anthony_irl]

Think that'd be javascript as AFAIK you can't do stuff like that with php as that event would be client side.