function changeDisplay(object_item)
{
	var the_item = document.getElementById(object_item);
	
	if (document.getElementById) 
	{ // DOM3 = IE5, NS6 
		if (the_item.style.display == 'none') 
			the_item.style.display = 'block';
		else
			the_item.style.display = 'none';		
	} 
	else 
	{ 
		if (document.layers) 
		{ // Netscape 4 
			if (the_item.display == 'none') 
				the_item.display = 'block'; 
			else
				the_item.display = 'none'; 
		} 
		else 
		{ // IE 4 
			if (the_item.style.display == 'none') 
				the_item.style.display = 'block';
			else
				the_item.style.display = 'none';
		} 
	} 
} 

function MM_validateForm() { //v4.0
  if (document.getElementById){
    var i,p,q,nm,test,num,min,max,errors='',args=MM_validateForm.arguments;
    for (i=0; i<(args.length-2); i+=3) { test=args[i+2]; val=document.getElementById(args[i]);
      if (val) { nm=val.name; if ((val=val.value)!="") {
        if (test.indexOf('isEmail')!=-1) { p=val.indexOf('@');
          if (p<1 || p==(val.length-1)) errors+=nm+',\n';
        } else if (test!='R') { num = parseFloat(val);
          if (isNaN(val)) errors+=nm+' must contain a number.\n';
          if (test.indexOf('inRange') != -1) { p=test.indexOf(':');
            min=test.substring(8,p); max=test.substring(p+1);
            if (num<min || max<num) errors+=nm+' must contain a number between '+min+' and '+max+'.\n';
      } } } else if (test.charAt(0) == 'R') errors += nm+',\n'; }
    }	
	if(document.getElementById('voorwaarden').checked == false){
		errors += 'Algemene voorwaarden\n';	
	}
	if (errors) alert('U heeft de volgende velden \nniet of niet juist ingevuld:\n\n'+errors);
    	document.MM_returnValue = (errors == '');	
} }

function MM_validateForm2() { //v4.0
  if (document.getElementById){
    var i,p,q,nm,test,num,min,max,errors='',args=MM_validateForm2.arguments;
    for (i=0; i<(args.length-2); i+=3) { test=args[i+2]; val=document.getElementById(args[i]);
      if (val) { nm=val.name; if ((val=val.value)!="") {
        if (test.indexOf('isEmail')!=-1) { p=val.indexOf('@');
          if (p<1 || p==(val.length-1)) errors+=nm+',\n';
        } else if (test!='R') { num = parseFloat(val);
          if (isNaN(val)) errors+=nm+' must contain a number.\n';
          if (test.indexOf('inRange') != -1) { p=test.indexOf(':');
            min=test.substring(8,p); max=test.substring(p+1);
            if (num<min || max<num) errors+=nm+' must contain a number between '+min+' and '+max+'.\n';
      } } } else if (test.charAt(0) == 'R') errors += nm+',\n'; }
    }	
	if (errors) alert('U heeft de volgende velden \nniet of niet juist ingevuld:\n\n'+errors);
    	document.MM_returnValue = (errors == '');	
} }