function element(id) {
	var e;
	if (document.getElementById) {
		e = document.getElementById(id);
	} else if (document.all) {
		e = document.all[id];
	} else {
		e = false; 
	}
	return e; 
}
function trim(str){
  return str.replace(/^\s+|\s+$/g, '');
}
var venster = '';
function openWindow(url, name, w, h, menubar, scroll){
	if(document.getElementById) {
		centerX = parseInt(screen.width / 2);
		centerY = parseInt(screen.height / 2);
	} else {
		centerX = parseInt(screen.availWidth / 2);
		centerY = parseInt(screen.availHeight / 2);
	}
	windowLeft = centerX - parseInt(w/2);
	windowTop = centerY - parseInt(h/2);
	parameters  = 'toolbar=0,location=0,resize=1,menubar=' + menubar;
	parameters += ',width=' + w + ',height=' + h + ',top=' + windowTop + ',left=' + windowLeft;
	if(scroll != null) parameters += ',scrollbars=1';
	venster = window.open(url, name, parameters);
	if(!venster.opener) venster.opener = self;
	if(window.focus){venster.focus()}
}
function showMenu(obj) {
    hideNav();
    var e = element(obj);
    if (e) {
        if(/navigatie/.test(e.className)) {
            e.style.display ='block';
        }
    }
}
function hideMenu(obj) {
    var e = element(obj);
    if (e) {
        if(/navigatie/.test(e.className)) {
            e.style.display ='none';
        }
    }
}
function hideNav() {
    var navs = document.getElementsByTagName('UL');
    for(i in navs) {
        if(/navigatie/.test(navs[i].className)) {
            navs[i].style.display ='none';
        }
    }
}
window.onload = function() { hideNav(); }

// form control
function validateForm(id) { 
    var formId, val, nm, checked=false, vgcheck=false, errors="";
    var regExpPostcode = /\d\d\d\d\s([a-zA-Z]{2})/;
    var regExpTelefoon = /\d\d\d..\d\d\d\d\d/;
    var regExpEmail = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
	var regExpUrl = /^(http:\/\/)+([a-zA-Z0-9_\.\-])+(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/;
    formId = element(id);
    for (i=0 ; i < formId.elements.length; i++) {
        if (formId.elements[i].type != "hidden") {
            val = formId.elements[i].value ;
            nm = formId.elements[i].id ;
            if (nm.indexOf("_Id") != -1) nm = nm.substring(0, nm.indexOf("_Id"));
            if(formId.elements[i].getAttribute('required') == 1) {
				if (val.length == 0){errors += "\n -in " + nm + " a ";
					if(nm.indexOf('e-mail') != -1){errors += "e-mailaddress";}
					else {errors += nm;}
				} else { 
        			//if(formId.elements[i].getAttribute('valuetype') == 'telnr' && !regExpTelefoon.test(val)) { errors += "\n -in " + nm + " een geldig telefoonnummer";}
        			//if(formId.elements[i].getAttribute('valuetype') == 'zipcode' && !regExpPostcode.test(val)) { errors += "\n -in " + nm + " een geldige postcode";}
					if (nm.indexOf('e-mail') != -1 && !regExpEmail.test(val)){errors += "\n -in " + nm + " a valid e-mailaddress";}
					//if (nm.indexOf('web') != -1 && !regExpUrl.test(val)){errors += "\n -in " + nm + " een geldig websiteadres";}
				}
			}else if (val.length != 0){
				//if(formId.elements[i].getAttribute('valuetype') == 'telnr' && !regExpTelefoon.test(val)) { errors += "\n -in " + nm + " een geldig telefoonnummer";}
				//if(formId.elements[i].getAttribute('valuetype') == 'zipcode' && !regExpPostcode.test(val)) { errors += "\n -in " + nm + " een geldige postcode";}
				if (nm.indexOf('e-mail') != -1 && !regExpEmail.test(val)){errors += "\n -in " + nm + " a valid e-mailaddress";}
				//if (nm.indexOf('web') != -1 && !regExpUrl.test(val)){errors += "\n -in " + nm + " een geldig websiteadres";}
			}}}	
	if(errors != ""){		
		alert('The folowing information is required:\n\n'+ errors +'\t\t\n\n');
		return false;
	}else{return true;}
}