one example:
<HTML>
<HEAD>
<SCRIPT>
function checkArrows (field, evt) {
var keyCode =
document.layers ? evt.which :
document.all ? event.keyCode :
document.getElementById ? evt.keyCode : 0;
var r = '';
if (keyCode == 39)
r += 'arrow right';
else if (keyCode == 40)
r += 'arrow down';
else if (keyCode == 38)
r += 'arrow up';
else if (keyCode == 37)
r += 'arrow left';
r += ' ' + keyCode;
alert(r);
return true;
}
</SCRIPT>
</HEAD>
<BODY>
<FORM NAME="formName">
<TEXTAREA NAME="aTextArea" ROWS="5" COLS="20" WRAP="soft" ONKEYDOWN="return checkArrows(this, event)">
click here and then use an arrow key.
</TEXTAREA>
</FORM>
</BODY>
</HTML>