Hide Layer if Texbox Length = 0?

[JEgbert]

I built a dynamic ajax suggest engine, and you would think I could
figure this out, but I am having a brain cramp. When I don't have any
characters in the search box, it shows a little blip of the layer
where the suggestion results go...

How do I make this go away? Something along the lines of

if ( document.getElementById('txtSearch').length == 0){
thelayer.style.display=(thelayer.style.display=="none");
}

???

Any help on this whole ordeal would be nothing less than
phenominal!

Thanks in advance!
JE