function a() {
  alert('asss');
}

function lessthan(number, tocompare) {
  if (number < tocompare) return true;
  else return false;
}

function greaterthan(number, tocompare) {
  if (number > tocompare) return true;
  else return false;
}

// fce pro nahrazeni textu v nejakem tagu -> chodi pro IE i FF
function setInnerText(obj, text) {
  if(document.all){
       obj.innerText = text;
  } else{
      obj.textContent = text;
  }
}

// snaha o zobrazeni modalniho dialogu pokud to nejde tj. neni IE tak se snazi
// zobrazit co nejvice osekane okno
function showDialog(url, width, height) {

    if (window.showModalDialog) {
        var ieFeatures = "dialogHeight:" + height + "px"
                       + "dialogWidth:" + width + "px"
                       + "edge:sunken;"
                       + "help:no;"
                       + "scroll:no;"
                       + "resizable:no;"
                       + "status:no;"
                       + "unadorned:no;";
        showModalDialog(url, window, ieFeatures);
    } else {
        var windowName = "sampleDialog"
        var mozillaFeatures = "width=" + width - 20 +","
                            + "height=" + height + ","
                            + "toolbar=no,"
                            + "location=no,"
                            + "directories=no,"
                            + "status=no,"
                            + "menubar=no,"
                            + "scrollbars=no,"
                            + "resizable=no,"
                            + "modal=yes";
        window.open(url, windowName, mozillaFeatures);
    }
    return false;
}

// event handlign functions are from
// http://www.soziologie.uni-halle.de/unger/SCRIPTs/workshop_internet/txt_js_322.html
// thx

function addEvent(obj, eventType, afunction, isCapture) {
  // W3C DOM
  if (obj.addEventListener) {
     obj.addEventListener(eventType, afunction, isCapture);
     return true;
  }
  // Internet Explorer
  else if (obj.attachEvent) {
     return obj.attachEvent("on"+eventType, afunction);
  }
  else return false;
}

function removeEvent(obj, eventType, afunction, isCapture) {
  if (obj.removeEventListener) {
     obj.removeEventListener(eventType, afunction, isCapture);
     return true;
  }
  else if (obj.detachEvent) {
     return obj.detachEvent("on"+eventType, afunction);
  }
  else return false;
}

// pouzito z opor predmetu PIS
// Detekce typu prohlizece spustenem na klientovi

var browIE=0;// prohlížeče
var browNetscape=1;
var browOpera=2;
var browName=browIE;
var browType = function () {
// získání typu prohlížeče
// parametry:nejsou
// návratová hodnota: true - povedlo se

if (navigator.appName=="Microsoft Internet Explorer") { 
  browName=browIE;
}  // IE
else if (navigator.appName=="Netscape") {
  // Netscape, Mozilla Firefox
  browName=browNetscape;
} // Netscape
else if (navigator.appName=="Opera") { // Opera
  browName=browOpera;
} // Opera
  
  return true;
}; // browType