function agreeTerms(formId)
	{
	
		form = document.getElementById(formId);
				
			if(form.checkbox.checked == false){
					
				alert('U moet het eens zijn met onze voorwaarden.');
					
				return false;
					
			}else{
					
				return true;
					
			}				
		}
					
	function swap ( div )
	{
	
		var div = document.getElementById ( div );
		
			if ( div.style.display == 'none' )
			{
			
				div.style.display = 'block';
				
			}else{
			
				div.style.display = 'none';
			}
			
		return true;				
	}
	
 function chck(welke)
  {
  
   var form = document.forms['bestanden'];
   
   if(document.getElementById('id'+welke).checked)
   
    document.getElementById('sel'+welke).style.backgroundColor='transparent';
	
   else
   
    document.getElementById('sel'+welke).style.backgroundColor='transparent';
 
  var aantal = 0;
  
  for(i=0; i < form.elements.length; i++)
   {
   
    if(form.elements[i].type == "checkbox" && form.elements[i].name != "alles" && form.elements[i].checked == false)
    aantal++;
	
   }
  
  if(aantal != 0)
  
   form.elements['alles'].checked = false;
   
  else
  
   form.elements['alles'].checked = true;  
   
  }

function chck_alles()
 {
 
  var form = document.forms['bestanden'];
  
  for(i=0; i < form.elements.length; i++)
   {
   
    if(form.elements[i].type == "checkbox" && form.elements[i].name != "alles")
     {
	 
      if(form.elements['alles'].checked)
       {
	   
        form.elements[i].checked = true;
        document.getElementById('sel'+form.elements[i].value).style.backgroundColor='transparent';
		
       }else{
	   
        form.elements[i].checked = false;
        document.getElementById('sel'+form.elements[i].value).style.backgroundColor='transparent';
		
       }
     }
   }
 }