function findObject(objectId)
{
	if(window.document.getElementById && window.document.getElementById(objectId))
		return window.document.getElementById(objectId);
	else if (window.document.all && window.document.all(objectId))
		return window.document.all(objectId);
	else if (window.document.layers && window.document.layers[objectId]) 
		return window.document.layers[objectId];
	else
		return null;
}

function getWindowHeight()
{
	var windowHeight = 0;
	if (typeof(window.innerHeight) == 'number')
		windowHeight = window.innerHeight;
	else
	{
		if (document.documentElement && document.documentElement.clientHeight)
			windowHeight = document.documentElement.clientHeight;
		else
		{
			if (document.body && document.body.clientHeight)
				windowHeight = document.body.clientHeight;
		}
	}
	return windowHeight;
}


function getFormData(formName)
{
	var _form = null;
	var _responseBody = '';
	var _elm = null;
		
	if (typeof(findObject)=='function')
	{
		_form = findObject(formName);
	}
	else
	{
		alert('Form object ' + formName + ' could not be found');
	}

	if (_form == null)
		return null;
		
	for(i=0;i<_form.elements.length;i++)
	{
		_elm = _form.elements[i];

		switch(_elm.type)
		{
			case 'submit'	: break;
			case 'checkbox' :
			case 'radio' :
			{
				if(_elm.checked == true)
					_responseBody += '&'+ encodeURIComponent(_elm.name)+'='+encodeURIComponent(_elm.value);
				break;
			}
			default :
			{
				_responseBody += '&'+ encodeURIComponent(_elm.name)+'='+encodeURIComponent(_elm.value);
				break;
			}
		}	
	}
	
	return _responseBody;
}

function submitForm(formname)
{
	try
	{
		var obj = findObject(formname);
		if (obj != null)
			obj.submit();
	}
	catch(e) {}

	return false;
}

<!--
window.onload = function() {
	setFooter();
	if (document.getElementById('spotlink') && document.getElementById('spotlight2')) { spotlight(); }
}

window.onresize = function() {
	setFooter();
}

var footercount = 0;
var browserName=navigator.appName;
var browserVersion=navigator.userAgent;

function setFooter() {
	if (document.getElementById) {
		var windowHeight = getWindowHeight()-4;  
		
		if (windowHeight > 0) {
			var topperHeight = document.getElementById('header').offsetHeight;
			var block1Height = document.getElementById('block_1').offsetHeight;
			if (document.getElementById('block_2'))
			{
				var block2Height = document.getElementById('block_2').offsetHeight;
			}
			else
			{
				var block2Height = 0;
			}
			var block3Height = document.getElementById('block_3').offsetHeight;
			var block4Height = document.getElementById('block_4').offsetHeight;
			var footerHeight = document.getElementById('footer').offsetHeight;

			if (block1Height<block2Height) {block1Height = block2Height; }
			if (block1Height<block3Height) {block1Height = block3Height; }
			if (block1Height<block4Height) {block1Height = block4Height; }
			
			if ((block1Height+topperHeight+footerHeight) < windowHeight) {
				document.getElementById('wrapper').style.height = windowHeight-topperHeight + 'px';
				document.getElementById('block_4').style.height = windowHeight-topperHeight-18 + 'px';
			} 
			else {
				document.getElementById('wrapper').style.height = block1Height + 'px';
				if (footercount<10) {
					document.getElementById('block_4').style.height = block1Height - 1 + 'px';
				}
			}
			
			//window.status = block1Height+', '+block2Height+', '+block3Height+', '+block4Height+', '+document.getElementById('wrapper').offsetHeight;
			window.status = footercount;
			
			//spotlink op positie zetten
			if (document.getElementById('spotlink')) {
				document.getElementById('spotlink').style.left = document.getElementById('block_1').offsetLeft + 'px';
				document.getElementById('spotlink').style.top = 0 + 'px';
				document.getElementById('spotlink').style.height = document.getElementById('wrapper').offsetHeight + 'px';

				if (document.getElementById('spotlight2'))
				{
					document.getElementById('spotlight2').style.left = document.getElementById('block_1').offsetLeft + 'px';
					document.getElementById('spotlight2').style.top = 0 + 'px';
					document.getElementById('spotlight2').style.height = document.getElementById('wrapper').offsetHeight + 'px';
				}
			}
			
			// In Explorer heeft de Footer horizontale positionering nodig 
			
			if ((browserName=="Microsoft Internet Explorer") && (browserVersion.indexOf('MSIE 7') == -1))
			{
				footercount = footercount +1;
				
				document.getElementById('bottom').style.position = 'absolute';
				document.getElementById('bottom').style.marginLeft = 0 + 'px';
				document.getElementById('bottom').style.Left = 0 + 'px';

				document.getElementById('footer').style.position = 'absolute';
				document.getElementById('footer').style.left = document.getElementById('wrapper').offsetLeft + 'px';	
				document.getElementById('footer').style.visibility = 'visible';
			}
		}
	}
}

function spotlight() {
	// Init animation 
	//setOpacity(image, 100);
	//var imageId = 'spotlight2';
	timer = window.setTimeout("fadeIn('spotlight2',0)", 5000);
	image = document.getElementById('spotlink');
}

var timer = 0;
var image = null;



function fadeIn(objId,opacity) {
	if (document.getElementById) {
		obj = document.getElementById(objId);
		if (opacity <= 100) {
			setOpacity(obj, opacity);
			opacity += 7; //fade speed
			window.setTimeout("fadeIn('spotlight2',"+opacity+")", 40);
		} else {
			//Fading is done
			setOpacity(obj, 100);
			window.setTimeout("fadeOut('spotlight2',100)", 5000);
			if (homelink2) {image.href = homelink2;}
		}
	}
}

function fadeOut(objId,opacity) {
    if (document.getElementById) {
		obj = document.getElementById(objId);
		if (opacity >= 0) {
			setOpacity(obj, opacity);
			opacity -= 7; //fade speed
			window.setTimeout("fadeOut('spotlight2',"+opacity+")", 40);
		} else {
			//Fading is done
			setOpacity(obj, 0);
			window.setTimeout("fadeIn('spotlight2',0)", 5000);
			if (homelink1) {image.href = homelink1;}
		}
	}
}

function setOpacity(obj, opacity) {
	opacity = (opacity == 100)?99.999:opacity;
	obj = document.getElementById('spotlight2');
	// IE/Win
	obj.style.filter = "alpha(opacity:"+opacity+")";
	// Safari<1.2, Konqueror
	obj.style.KHTMLOpacity = opacity/100;
	// Older Mozilla and Firefox
	obj.style.MozOpacity = opacity/100;
	// Safari 1.2, newer Firefox and Mozilla, CSS3
	obj.style.opacity = opacity/100;
}



		
function getWindowWidth() {
	var windowWidth = 0;
	if (typeof(window.innerWidth) == 'number') {
		windowWidth = window.innerWidth;
	}
	else {
		if (document.documentElement && document.documentElement.clientWidth) {
			windowWidth = document.documentElement.clientWidth;
		}
		else {
			if (document.body && document.body.clientWidth) {
				windowWidth = document.body.clientWidth;
			}
		}
	}
	return windowWidth;
}

function getStyleObject(objectId) {
    // cross-browser function to get an object's style object given its id
    if(document.getElementById && document.getElementById(objectId)) {
	// W3C DOM
	return document.getElementById(objectId).style;
    } else if (document.all && document.all(objectId)) {
	// MSIE 4 DOM
	return document.all(objectId).style;
    } else if (document.layers && document.layers[objectId]) {
	// NN 4 DOM.. note: this won't find nested layers
	return document.layers[objectId];
    } else {
	return false;
    }
} // getStyleObject

function changeObjectVisibility(objectId, newVisibility) {
    // get a reference to the cross-browser style object and make sure the object exists
    var styleObject = getStyleObject(objectId);
    if(styleObject) {
	styleObject.visibility = newVisibility;
	return true;
    } else {
	// we couldn't find the object, so we can't change its visibility
	return false;
    }
} // changeObjectVisibility

function swapObjectDisplay(objectId) {
    // get a reference to the cross-browser style object and make sure the object exists
    var styleObject = getStyleObject(objectId);
    window.status = styleObject.display;
    icn = 'img_'+objectId;
    
    
    if(styleObject.display=='block') {
		styleObject.display = 'none';
		document[icn].src = 'images/icn_treeplus_bl_9.gif';
    } else {
		styleObject.display = 'block';
		document[icn].src = 'images/icn_treemin_bl_9.gif';
    }
    footercount=0;
    setFooter();
} // swapObjectDisplay


//Get Element by Class Name from: http://www.robertnyman.com/2005/11/07/the-ultimate-getelementsbyclassname/
function getElementsByClassName(oElm, strTagName, strClassName){
    var arrElements = (strTagName == "*" && oElm.all)? oElm.all : oElm.getElementsByTagName(strTagName);
    var arrReturnElements = new Array();
    strClassName = strClassName.replace(/\-/g, "\\-");
    var oRegExp = new RegExp("(^|\\s)" + strClassName + "(\\s|$)");
    var oElement;
    for(var i=0; i<arrElements.length; i++){
        oElement = arrElements[i];      
        if(oRegExp.test(oElement.className)){
            arrReturnElements.push(oElement);
        }   
    }
    return (arrReturnElements)
}

var newD = 'none';
var blockDisplay = 'table-row';
if (browserName=="Microsoft Internet Explorer"){
	blockDisplay = 'block';
} 
function swapClassDisplay(objectClass) {
	var styleObject = getElementsByClassName(document, 'tr', objectClass);
    icn = 'img_'+objectClass;
	if(styleObject[0].style.display==blockDisplay) {
		newD = 'none';
		document[icn].src = 'images/icn_treeplus_9.gif'
	} else {
		newD = blockDisplay;
		document[icn].src = 'images/icn_treemin_9.gif'
	}
    //alert(styleObject[1].style.display);
    
    for (var i=0; i < styleObject.length; i++) {
	    styleObject[i].style.display = newD;
    }
    footercount=0;
    setFooter();
}


function Search()
{
	var querystring = '';
	var maand = findObject("maand");
	if ((maand != null) && (maand.value != "0"))
	{
		querystring += '&maand=' + maand.value;
	}

	var genre = findObject("genre");
	if ((genre != null) && (genre.value != "0"))
	{
		querystring += '&genre=' + genre.value;
	}

	var composer = findObject("composer");
	if ((composer != null) && (composer.value != "0"))
	{
		querystring += '&componist=' + composer.value;
	}

	var zoek = findObject("zoek");
	if ((zoek != null) && (zoek.value != ""))
	{
		querystring += '&zoek=' + zoek.value;
	}

	var vandag = findObject("vandag");
	if ((vandag != null) && (vandag.value != "0"))
	{
		querystring += '&vandag=' + vandag.value;
	}

	var vanmaand = findObject("vanmaand");
	if ((vanmaand != null) && (vanmaand.value != "0"))
	{
		querystring += '&vanmaand=' + vanmaand.value;
	}

	var vanjaar = findObject("vanjaar");
	if ((vanjaar != null) && (vanjaar.value != "0"))
	{
		querystring += '&vanjaar=' + vanjaar.value;
	}

	var totdag = findObject("totdag");
	if ((totdag != null) && (totdag.value != "0"))
	{
		querystring += '&totdag=' + totdag.value;
	}

	var totmaand = findObject("totmaand");
	if ((totmaand != null) && (totmaand.value != "0"))
	{
		querystring += '&totmaand=' + totmaand.value;
	}

	var totjaar = findObject("totjaar");
	if ((totjaar != null) && (totjaar.value != "0"))
	{
		querystring += '&totjaar=' + totjaar.value;
	}
	
	if (querystring.length > 0)
	{
		querystring = '?' + querystring.substring(1);
	}
	
	document.location.href = 'zoek.aspx' + querystring;
}
-->