// parse the cookie name and value
    public bool parseCookieNameValue(string ckNameValueExpr, out pairItem pair)
    {
        bool parsedOK = false;
        if (ckNameValueExpr == "")
        {
            pair.key = "";
            pair.value = "";
            parsedOK = false;
        }
        else
        {
            ckNameValueExpr = ckNameValueExpr.Trim();

            int equalPos = ckNameValueExpr.IndexOf('=');
            if (equalPos > 0) // is valid expression
            {
                pair.key = ckNameValueExpr.Substring(0, equalPos);
                pair.key = pair.key.Trim();
                if (isValidCookieName(pair.key))
                {
                    // only process while is valid cookie field
                    pair.value = ckNameValueExpr.Substring(equalPos + 1);
                    pair.value = pair.value.Trim();
                    parsedOK = true;
                }
                else
                {
                    pair.key = "";
                    pair.value = "";
                    parsedOK = false;
                }
            }
            else
            {
                pair.key = "";
                pair.value = "";
                parsedOK = false;
            }
        }
        return parsedOK;
    }

    

        //string[] expressions = cookieStr.Split(";".ToCharArray(),StringSplitOptions.RemoveEmptyEntries);
        //refer: http://msdn.microsoft.com/en-us/library/b873y76a.aspx
        string[] expressions = cookieStr.Split(new char[] { ';' }, StringSplitOptions.RemoveEmptyEntries);
        //get cookie name and value
        pairItem pair = new pairItem();
        if (parseCookieNameValue(expressions[0], out pair))
        {