PayPal.Invoice.Model.GetInvoiceDetailsRequest.ToNVPString C# (CSharp) Method

        public string ToNVPString(string prefix)
        {
            StringBuilder sb = new StringBuilder();
            if (this.requestEnvelope != null)
            {
                    string newPrefix = prefix + "requestEnvelope" + ".";
                    sb.Append(this.requestEnvelopeField.ToNVPString(newPrefix));
            }
            if (this.invoiceID != null)
            {
                    sb.Append(prefix).Append("invoiceID").Append("=").Append(HttpUtility.UrlEncode(this.invoiceID, BaseConstants.ENCODING_FORMAT)).Append("&");
            }
            if (this.invoiceNumber != null)
            {
                    sb.Append(prefix).Append("invoiceNumber").Append("=").Append(HttpUtility.UrlEncode(this.invoiceNumber, BaseConstants.ENCODING_FORMAT)).Append("&");
            }
            return sb.ToString();
        }

 /**
   *AUTO_GENERATED
  	  */
 public GetInvoiceDetailsResponse GetInvoiceDetails(GetInvoiceDetailsRequest getInvoiceDetailsRequest, string apiUserName)
 {
     string response = Call("GetInvoiceDetails", getInvoiceDetailsRequest.ToNVPString(""), apiUserName);
     NVPUtil util = new NVPUtil();
     return GetInvoiceDetailsResponse.CreateInstance(util.ParseNVPString(response), "", -1);
 }