window.setTimeout('keepalive()', 180000)

function keepalive() {
	xhtmlReq('keepalive.asp')
	window.setTimeout('keepalive()', 180000)
}

function xhtmlReq(f_sUrl) {
	var oXMLHTTP

	if (window.XMLHttpRequest) {
		oXMLHTTP = new XMLHttpRequest()
		oXMLHTTP.open("GET", f_sUrl, false)
		try {
			oXMLHTTP.send(null)
			return oXMLHTTP.responseText
		} catch(e) {
			alert('mislukt: ' + e)
		}
	} else if (window.ActiveXObject) {
		oXMLHTTP = new ActiveXObject("Microsoft.XMLHTTP")
		if (oXMLHTTP) {
			oXMLHTTP.open("GET", f_sUrl, false)
			try  {
				oXMLHTTP.send()
				return oXMLHTTP.responseText
			} catch (e) {
				alert('mislukt: ' + e)
			}
		}
	}
}

function checkEnter(evt) {
	var evt = (evt) ? evt : ((event) ? event : null);
	var node = (evt.target) ? evt.target : ((evt.srcElement) ? evt.srcElement : null);
	var key

	if(window.event)
		key = window.event.keyCode;
	else
		key = evt.which;

	if (key == 13) {
		if (node.id == 'textfield') {
			checkValues()
		} else
			return true
	}
}

document.onkeypress = checkEnter;

function dispMenu(f_intId) {
    if (document.getElementById('menu' + f_intId).style.display == 'none' || document.getElementById('menu' + f_intId).style.display == '') {
        document.getElementById('img' + f_intId).src = 'images/button_minus.gif'
        document.getElementById('menu' + f_intId).style.display = 'block'
        document.getElementById('li' + f_intId).style.fontWeight = 'bold'
    } else {
        document.getElementById('img' + f_intId).src = 'images/button_plus.gif'
        document.getElementById('menu' + f_intId).style.display = 'none'
        document.getElementById('li' + f_intId).style.fontWeight = 'normal'
    }
}