function error(item, text) {
        if (flag) return;
        flag = true;
        window.alert(text);
        item.focus();
}

function isFilled(item) {
        if ((item=="")||(item==null))
                return false;
        return true;
}

function isNum(item) {
		var NumberString = "0123456789";
		for (var k = 0; k < item.length; k++)
			{
				var c = item.substring(k, k+1);
				if (NumberString.indexOf(c) == -1)
					{
					return false;			
					}
			}
				return true;			
	}

function isBlank(itemvalue) {
		if (itemvalue.length == 0)
			return true;
        else 
			return isNum(itemvalue);
}        

function isEmailValid(item) 
{
	var l = item.value.length;
	var at = item.value.indexOf("@");
	var dot = item.value.indexOf(".",at+1);
	if (((at < 1)||(dot <= at+1))||(dot == l-1)) 
		return false;
	return true;
}