function Browser() {
  var ua, s, i;
  this.isIE    = false;  // Internet Explorer
  this.isOP    = false;  // Opera
  this.isNS    = false;  // Netscape
  this.version = null;
  ua = navigator.userAgent;

  s = "Opera";
  if ((i = ua.indexOf(s)) >= 0) {
    this.isOP = true;
    this.version = parseFloat(ua.substr(i + s.length));
    return;
  }
  s = "Netscape6/";
  if ((i = ua.indexOf(s)) >= 0) {
    this.isNS = true;
    this.version = parseFloat(ua.substr(i + s.length));
    return;
  }
  // Treat any other "Gecko" browser as Netscape 6.1.
  s = "Gecko";
  if ((i = ua.indexOf(s)) >= 0) {
    this.isNS = true;
    this.version = 6.1;
    return;
  }
  s = "MSIE";
  if ((i = ua.indexOf(s))) {
    this.isIE = true;
    this.version = parseFloat(ua.substr(i + s.length));
    return;
  }
}

var vbrowser = new Browser();

function popUp(url,largeur,hauteur,scrolling,nom)
{
  window.open(url, nom,'width=' + largeur + ',height=' + hauteur + ',left='+(Math.round((screen.width-largeur)/2))+',top='+(Math.round((screen.height-hauteur)/2))+',scrollbars='+scrolling);	
}