function prepni(obrazok, element)
	{
		if (element.style.display=="none")
		{
			element.style.display="block";
			obrazok.src = "pictures/minus.gif";
		}
		else 
		{
			element.style.display="none";	
			obrazok.src = "pictures/plus.gif";
		}
	}
	
function zmenFormular(naKtory)
	{
	if (naKtory == "osoba")
		{
		document.getElementById("uzivatel_spolocnost_t").style.display = "none";
		document.getElementById("uzivatel_ico_t").style.display = "none";
		document.getElementById("uzivatel_dic_t").style.display = "none";
		document.getElementById("uzivatel_icdph_t").style.display = "none";
		document.getElementById("uzivatel_obreg_t").style.display = "none";
		document.getElementById("uzivatel_spolocnost").style.display = "none";
		document.getElementById("uzivatel_ico").style.display = "none";
		document.getElementById("uzivatel_dic").style.display = "none";
		document.getElementById("uzivatel_icdph").style.display = "none";
		document.getElementById("uzivatel_obreg").style.display = "none";
		}
	if (naKtory == "sro" || naKtory == "as" || naKtory == "zivnostnik" || naKtory == "ine")
		{
		document.getElementById("uzivatel_spolocnost_t").style.display = "inline";
		document.getElementById("uzivatel_ico_t").style.display = "inline";
		document.getElementById("uzivatel_dic_t").style.display = "inline";
		document.getElementById("uzivatel_icdph_t").style.display = "inline";
		document.getElementById("uzivatel_obreg_t").style.display = "inline";
		document.getElementById("uzivatel_spolocnost").style.display = "inline";
		document.getElementById("uzivatel_ico").style.display = "inline";
		document.getElementById("uzivatel_dic").style.display = "inline";
		document.getElementById("uzivatel_icdph").style.display = "inline";
		document.getElementById("uzivatel_obreg").style.display = "inline";
		}
	}
	
function kontrola_Datumu()
	{
		datum_od = document.getElementById("kosik_od").value;
		datum_do = document.getElementById("kosik_do").value;
		
		if(!isDate(datum_od,"yyyy-mm-dd") || !isDate(datum_do,"yyyy-mm-dd"))
			{
				window.alert('Nezadali jste datum v požadovaném formátu!');
				return false;
			}
		else
			{
				if(compareDates(datum_od,"yyyy-mm-dd",datum_do,"yyyy-mm-dd") == 0)
					{
						return true;
					}
				else	
					{
						window.alert('Datum-od musí být dříve než datum-do!');
						return false;
					}
			}
	}