PayPal.IPNMessage.IpnValue C# (CSharp) Method

        public string IpnValue(string ipnName)
        {
            return this.nvcMap[ipnName];
        }

 public void IPNParameter()
 {
     NameValueCollection nvc = HttpUtility.ParseQueryString(ipnMsg);
     IPNMessage ipn = new IPNMessage(nvc);
     string parameter = ipn.IpnValue("fees_payer");
     Assert.AreEqual("EACHRECEIVER", parameter);
 }