function hide(id) { document.getElementById(id).style.display = 'none'; }
function show(id) { document.getElementById(id).style.display = 'block'; }
function hideDiv(div) { div.style.display = 'none'; }
function showDiv(div) { div.style.display = 'block'; }
function enable(id) { document.getElementById(id).removeAttribute('readonly'); }
function disable(id) { document.getElementById(id).setAttribute('readonly',true); }
function toggle(id) { if (document.getElementById(id).style.display == 'none' || (document.getElementById(id).className == 'hidden' && document.getElementById(id).style.display == '')) { show(id); } else { hide(id); } }
function getvalue(id) { return document.getElementById(id).value; }
function setvalue(id,val) { return document.getElementById(id).value = val; }

function isset(variable_name) {
	try {
		if (typeof(eval(variable_name)) != 'undefined')
			if (eval(variable_name) != null)
				return true;
	} catch(e) { }
	return false;
}

function addEvent(elm, evType, fn, useCapture){
    if (elm.addEventListener)
    {
      elm.addEventListener(evType, fn, useCapture);
      return true;
    } else if (elm.attachEvent) {
      var r = elm.attachEvent('on' + evType, fn);
      return r;
    } else {
      elm['on' + evType] = fn;
    }
}

function removeDiv(elm) {
	elm.parentNode.removeChild(elm);
}

function cloneBefore(original, copycat) {
	var newthing = document.createElement('div');
	newthing.innerHTML = original.innerHTML;
	newthing.style.display = 'block';
	copycat.parentNode.insertBefore(newthing, copycat);
}