var arrNavbar, arrNavbarOn, arrNavbarOff;
var strNavbarDir;

strNavbarDir = "images/navbar/";
arrNavbar = new Array();
arrNavbarOn =new Array();
arrNavbarOff = new Array();;
arrNavbar[0] = "home";
arrNavbar[1] = "our_products";
arrNavbar[2] = "advantages";
arrNavbar[3] = "order";
arrNavbar[4] = "contact";
function cacheNavbar()
{
	for(var i=0; i< arrNavbar.length; i ++)
	{
		arrNavbarOn[i] = new Image();
		arrNavbarOn[i].src = strNavbarDir + arrNavbar[i] +"_on.gif";
		arrNavbarOff[i] = new Image();
		arrNavbarOff[i].src = strNavbarDir + arrNavbar[i] +"_off.gif";
	}
}
function swapNavbarImg(oImg, nIndex, bOn)
{
	try
	{
		oImg.src = bOn ? arrNavbarOn[nIndex].src : arrNavbarOff[nIndex].src;
	}
	catch(excpt)
	{
	}
}
function isEmpty(str)
{
	var regEmpty = /[^ \t\r\n]+/;
	return !regEmpty.test(str);
}
function isEmail(str) 
{
	var emailReg = /^[a-z][a-z-_0-9\.]+@[a-z-_=>0-9\.]+\.[a-z]{2,3}$/i;
	return emailReg.test(str);
}
function isZipcode(str)
{
	var regZipcode = /^[0-9]{5}$/;
	return regZipcode.test(str);
}
function onSubmitMessage(oForm)
{
	var strEmail, strZipcode;
	
	strEmail = oForm.elements["Email"].value;
	if(isEmpty(strEmail))
	{
		alert("Please enter your e-mail address!");
		oForm.elements["Email"].focus();
		return false;
	}
	else
		if(!isEmail(strEmail))
		{
			alert("Please enter a valid e-mail address!");
			oForm.elements["Email"].focus();
			return false;
		}
	
	strZipcode = oForm.elements["Zipcode"].value;
	if(!isEmpty(strZipcode))
		if(!isZipcode(strZipcode))
		{
			alert("Please enter a valid zipcode!");
			oForm.elements["Zipcode"].focus();
			return false;
		}
	
	return true;
}