Prevent page postback when user hits enter

Prevent page postback when user hits enter

I have a web form which when the user hits enter, the page will be posted
back. Here's the thing: when the user clicks on the form, a control will
be focused (my mouse pointer changes into the one for when you are about
to click an input control) and when the enter is hit, my page will reload.
Is there a way to capture the press of any key not mattering where the
user clicks on?