I'm trying my hand in asp.net. I have a dropdown list in my page.There's a button below this dropdown.Both this control are in a panel.
What I'm trying to do is when I select on dropdown list to change the value I want to shift buttons below as in when you go to select dropdown, the list opens and elongates, when this elongates I want to push the button below and when I select an item in dropdown put the buttons back.
You could probably trap clicks or focus events to move things around on the client side (see http://www.w3schools.com/tags/tag_select.asp for event options) and then show/hide an empty div or something like that, but in general I'd avoid "features" like this. It's a pain to build, it isn't expected behaviour by the user, and it may also be a pain to maintain cross-browser support for.
Without seeing what you're trying to do, it's difficult to say, but I'd recommend there may be some layout options you could look at to get around whatever issue the dropdown is causing.