// Begin
function checkrequired(which) {
  var pass=true;
  if (document.images) {
    for (i=0;i<which.length;i++) {
      var tempobj=which.elements[i];
      if (tempobj.name.substring(0,8)=="required") {
        if (((tempobj.type=="text"||tempobj.type=="textarea")&&
              tempobj.value=='')||(tempobj.type.toString().charAt(0)=="s"&&
              tempobj.selectedIndex==0)) {
          pass=false;
          break;
          }
        }
      }
    }
  //pass = true;
  if (!pass) {
    shortFieldName=tempobj.name.substring(8,30).toUpperCase();
    alert("U moet het "+shortFieldName+" vakje nog invullen.");
    return false;
    }
  else {
    var datum = parseInt( which.requiredjaar.value ) * 10000;
    var aMaanden = new Array();
    aMaanden['januari'] = 1;
    aMaanden['februari'] = 2;
    aMaanden['maart'] = 3;
    aMaanden['april'] = 4;
    aMaanden['mei'] = 5;
    aMaanden['juni'] = 6;
    aMaanden['juli'] = 7;
    aMaanden['augustus'] = 8;
    aMaanden['september'] = 9;
    aMaanden['oktober'] = 10;
    aMaanden['november'] = 11;
    aMaanden['december'] = 12;
    datum += parseInt( aMaanden[ which.requiredmaand.value.toLowerCase() ] ) * 100;
    datum += parseInt( which.requireddag.value );

    var myDate = new Date();
    var vandaag = parseInt( myDate.getFullYear() ) * 10000;
    vandaag += parseInt( myDate.getMonth() + 1 ) * 100;
    vandaag += parseInt( myDate.getDate() );

    //alert('Datum: ' +datum+ '\nVandaag: ' +vandaag);

    if ( datum <= vandaag ) {
      alert('De datum die u heeft gekozen ligt in het verleden. U mag alleen reserveren voor vandaag of later');
      return false;      
      }
    }
  return true;
  }
//  End -->

<!--
function MM_showHideLayers() { //v3.0
  var i,p,v,obj,args=MM_showHideLayers.arguments;
  for (i=0; i<(args.length-2); i+=3) if ((obj=MM_findObj(args[i]))!=null) { v=args[i+2];
    if (obj.style) { obj=obj.style; v=(v=='show')?'visible':(v='hide')?'hidden':v; }
    obj.visibility=v; }
}
//-->

function MM_findObj(n, d) { //v4.01
  var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
    d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
  if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
  for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
  if(!x && d.getElementById) x=d.getElementById(n); return x;
}