function trim(str, chars) {
    return ltrim(rtrim(str, chars), chars);
}

function ltrim(str, chars) {
    chars = chars || "\\s";
    return str.replace(new RegExp("^[" + chars + "]+", "g"), "");
}

function rtrim(str, chars) {
    chars = chars || "\\s";
    return str.replace(new RegExp("[" + chars + "]+$", "g"), "");
}

function ukaz(prvni,elementID)
{
	if(document.getElementById(prvni).value == "0") {
		document.getElementById(elementID).style.display = "";

	}else{
		document.getElementById(elementID).style.display = "none";
	}
}

function smilie(smkey) 
{
  document.post.vzkaz.value += smkey+" ";
  document.post.vzkaz.focus();
}

function obrazek()
{
  x=prompt('Vložte URL adresu obrázku', ''); 
  x=trim(x);
  if(x) {
    document.post.vzkaz.value += "[img]"+ x +"[/img]";
    document.post.vzkaz.focus();
  }
}

function odkaz()
{
  x=prompt('Vložte URL adresu', ''); 
  x=trim(x);
  if(x) {
    document.post.vzkaz.value += "[a]"+ x +"[/a]";
    document.post.vzkaz.focus();
  }
}

function OpenUrl(strURL,nW,nH,sScroll){
	var objWin = window.open(strURL,"Info","scrollbars="+sScroll+",resizable=yes,height="+nH+"px,width="+nW+"px,left=10px,top=10px");
	return (typeof(objWin)!="object")?true:false;
}

function hideMsg(){
  el=document.getElementById('cart-message');
  if(!el) {
    return false;
  }
  el.innerHTML = "";
  el.style.display = "none";	
}