var layer = new String();
var style = new String();
var menu  = new String();
var timerID = null;
// function checkBrowser(){
// Opredelaem tip brousera dlya otobrajenia sloyev
if (navigator.userAgent.indexOf("MSIE") >= 0){
 layer = "all[";
 style = "].style";
} else if(navigator.userAgent.indexOf("Mozilla") >= 0){
 layer = "getElementById(";
 style = ").style";
} else {
 layer = "layers[";
 style = "]";
}
// }

function vizmenu(vismenu){
// otobrajenie menu 
 for (var i=1; i<5; i++){
   if (vismenu == i.toString()){
// alert(document.td1.currentStyle.backgroundColor);
//     document.all['menu' + i].style.top = 10;
  eval("document." + layer + "'menu" + vismenu + "'" + style + ".visibility='visible'");
   } else {
  eval("document." + layer + "'menu" + i + "'" + style + ".visibility='hidden'");
   }
 }
// Zakrytie menu posle 10 sekund pokaza
 menu = vismenu;
 clearTimeout(timerID);
 timerID = setTimeout('hidmenu(menu)', 10000);
}

function hidmenu(vismenu){
// sokrytie menu
// document.all['menu' + vismenu].style.visibility='hidden';
  eval("document." + layer + "'menu" + vismenu + "'" + style + ".visibility='hidden'");
}

function chkDate(objectP) {
// format daty dd-mm-gggg
   var poleString = new String (objectP.value);
   var lenString = poleString.length;
   if (lenString < 10) {
      return false;
   }
   var checkString = new String('1234567890');
   var oldString = new String (poleString.substring(6,10) + poleString.substring(3,5) + poleString.substring(0,2));
   for (var i=0; i<9; i++){   
     if (checkString.indexOf(oldString.charAt(i))<0){
//          alert(oldString.charCodeAt(i));
         return false;
     }
   }
   return true;
}

var change=0;
function blink(){ // blink text
  if (change==0){
	blinktext.style.color="blue";
  } else {
	blinktext.style.color="green";
  }
  change = (change==0) ? 1 : 0;
}