var isVisible = false;
function hidelay(){
	if (isVisible == false) {
		document.getElementById("nl-subsc-first").className='active';
		isVisible = true;	
	}
	else {
		document.getElementById("nl-subsc-first").className='inactive';
		isVisible = false;
	}
}


//zentriertes popup fenster:  
//in den link:  onclick="NewWindow(this.href,'name','breite','h�he','yes');return false;" 
// das yes im aufruf erlaubt das scrollen, no f�r kein scrollen

function NewWindow(mypage, myname, w, h, scroll) {
var winl = (screen.width - w) / 2;
var wint = (screen.height - h) / 2;
winprops = 'height='+h+',width='+w+',top='+wint+',left='+winl+',scrollbars='+scroll+',resizable=no' //resizable=yes ist die alternative
win = window.open(mypage, myname, winprops)
if (parseInt(navigator.appVersion) >= 4) { win.window.focus(); }
}

function isInteger(val)
{
    if(val==null)
    {
        return false;
    }
    if (val.length==0)
    {
        return false;
    }
    for (var i = 0; i < val.length; i++) 
    {
        var ch = val.charAt(i)
        if (i == 0 && ch == "-")
        {
            continue
        }
        if (ch < "0" || ch > "9")
        {
            return false
        }
    }
    return true
}

function checkValues() {
	var last_name = document.getElementById('last_name').value;
  var first_name = document.getElementById('first_name').value;
  var company = document.getElementById('company').value;
  var address = document.getElementById('address').value;
  var zip = document.getElementById('zip').value;
  var city = document.getElementById('city').value;
  var phone = document.getElementById('phone').value;
  var email = document.getElementById('email').value;
  var tickets = document.getElementById('tickets').value;

	if(last_name==""||first_name==""||company==""||address==""||zip==""||city==""||phone==""||email==""||tickets=="") {
    alert("Bitte füllen Sie alle Felder aus.");
    return false;
  } else {
    if(isInteger(tickets) && tickets>0) {
      return true;
    } else {
      alert("Bitte die Anzahl der Karten als Ziffer angeben.")
      return false;
    }
  }
}