Prevent scrolling with arrow keys

This code does the trick:

JavaScript

<script type="text/javascript">
  function focusOnIframe(iFrameID) {
    if (frames[iFrameID]!=undefined)
      frames[iFrameID].focus(); // Works in all browser, except Firefox
    else
      document.getElementById(iFrameID).focus();  // Works in Firefox
  }
</script>

HTML (example)

<input type="button" id="setfocus" value="Set focus" onclick="focusOnIframe('myiframe')" />

<p>Bla<br />Bla<br />Bla<br />Bla<br />Bla<br /></p>  <!-- Just some filler -->

<iframe id="myiframe" src="yourpage.html"></iframe>

<p>Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br />Bla<br /></p>  <!-- Just some filler -->

I've tested it in Firefox 3.6.6, Iron 5.0.380, Opera 10.60, IE 6 and IE 8.