function GetBrowserType()
{
	if (navigator.userAgent.indexOf("Opera")!=-1 && document.getElementById) return "OP"; 
	if (document.all) return "IE"; 
	if (document.layers) return "NN"; 
	if (!document.all && document.getElementById) return "MO"; 
}

function ShowHideLayer(id, action, displayaction)
{
    var type = GetBrowserType();
    if (type=="IE")
	{
	  eval("document.all." + id + ".style.visibility='" + action + "'");
	  eval("document.all." + id + ".style.display='" + displayaction + "'");
	}
	if (type=="NN") 
	{
		eval("document." + id + ".visibility='" + action + "'");
		eval("document." + id + ".display='" + displayaction + "'");
	}
	if (type=="MO" || type=="OP") 
    {
		eval("document.getElementById('" + id + "').style.visibility='" + action + "'");
		eval("document.getElementById('" + id + "').style.display='" + displayaction + "'");
	}
} 

function CheckManatoryFields(id, name)
{
	var type = GetBrowserType();
    if (type=="IE")
	{
	  if(eval("document.all." + id + ".value==''"))
	  {
	    alert("Feld '" + name + "' muss ausgefüllt werden.");
		return false;
	  }
	}
	if (type=="NN") 
	{
		return false;
	}
	if (type=="MO" || type=="OP") 
    {
	return false;
	}
	return true;
}