function EMail(s)
{
	var a = false;
	var res = false;
	if(typeof(RegExp) == 'function'){
		var b = new RegExp('abc');
		if(b.test('abc') == true){
			a = true;
		}
	}
	
	if(a == true){
		reg = new RegExp('^([a-zA-Z0-9\\-\\.\\_]+)'+'(\\@)([a-zA-Z0-9\\-\\.]+)'+'(\\.)([a-zA-Z]{2,4})$');
		res = (reg.test(s));
	}else{
		res = (s.search('@') >= 1 && s.lastIndexOf('.') > s.search('@') && s.lastIndexOf('.') >= s.length-5);
	}
	return(res);
}

function checkRequired(oForm) {
  var pass=true;
  if (document.images) {
    for (i=0;i<oForm.length;i++) {
      var tempobj=oForm.elements[i];
      if (tempobj.name.substring(0,5)=="__req") {
    	  if (!checkField(tempobj, oForm, tempobj.name.substring(5,tempobj.name.length).toUpperCase())) {
    		  pass=false;
    		  break;
    	  }
    	}
    }
  }
  return pass;
}

function checkField(field, oForm, fieldname) {
  var pass=true;
  if (((field.type=="text"||field.type=="textarea")&&
        field.value=='')||(field.type.toString().charAt(0)=="s"&&
        field.selectedIndex==0)) {
          pass=false;
  }
  if (field.type=="checkbox") {
    if (field.checked != true) {
      pass=false;
    }
  }
  if (field.type=="radio") {
    var radiogroup = oForm.elements[field.name];
    var itemchecked = false;
    for(var j = 0 ; j < radiogroup.length ; ++j) {
      if(radiogroup[j].checked) {
        itemchecked = true;
      }
    }
    if(!itemchecked) { 
      pass=false;
    }
  }
  if (field.name.toLowerCase()=="__reqemail") {
    if (!EMail(field.value)) {
          pass=false;
    }
  }
	
  if (!pass) {
    alert("Controleert u alstublieft het "+fieldname+" invoerveld, dit is een verplicht invoerveld.");
    field.focus();
    return false;
  }
  else
    return true;
}

for (var i=0;i<document.forms.length;i++) {
	var action = document.forms[i].action.toLowerCase();
  if(action.substr(0,11)=="/submit.asp" || action.substr(0,19)=="/server/submit.aspx"){
    eval("dummy"+i+" =  new Function(\"return\");");
    if(document.forms[i].onsubmit) {
      eval("dummy"+i+"=document.forms[i].onsubmit;");
    }
    eval("document.forms[i].onsubmit = new Function(\"dummy"+i+"();return checkRequired(this);\");");
  }
}