<html> 
<head> 
<title>Checkbox Event Handler - Happy Codings :-) JavaScript Code Examples</title> 
<style type="text/css"> 
#myGroup {visibility:hidden} 
</style> 
<script type="text/javascript"> 
function toggle(chkbox, group) { 
    var visSetting = (chkbox.checked) ? "visible" : "hidden"; 
    document.getElementById(group).style.visibility = visSetting; 
} 
function swap(radBtn, group) { 
    var modemsVisSetting = (group == "modems") ? ((radBtn.checked) ? "" : "none") : "none"; 
    document.getElementById("modems").style.display = modemsVisSetting; 
} 
</script> 
</head> 
<body> 
<form> 
<input type="checkbox" name="monitor" onclick="toggle(this, 'myGroup')" />Monitor
<span id="myGroup">
  <input type="radio" />15" 
</span>
</form> 
</body> 
</html>
