InfusionGateway.cs

using Microsoft.Win32;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace InfusionDemo
{
    class Program
    {
        static void Main(string[] args)
        {
            dynamic gateway = GatewayHelper.GetGateway();
            gateway.login("My Test Application");

            Console.WriteLine("Logged in");

            int nextInv = gateway.nextinv(1);

            Console.WriteLine("Next invoice number {0}", nextInv);

            Console.WriteLine("Press any key to continue");
            Console.ReadKey();
        }
    }


    public static class GatewayHelper
    {
        public static dynamic GetGateway()
        {
            // Attempt to get the latest gateway version registered on the server
            string latestGateway = GetLatestRegisteredGateway();
            if (string.IsNullOrWhiteSpace(latestGateway))
            {
                throw new Exception("A registered Infusion Gateway DLL could not be found");
            }
            // Create the gateway object
            Type gatewayType = Type.GetTypeFromProgID(latestGateway);
            dynamic ibsGw = Activator.CreateInstance(gatewayType);
            // Set the Infusion data path
            ibsGw.setpath(@"C:\Infusion\data");
            return ibsGw;
        }


        /// <summary>
        /// Gets the registered gateways from the registry.
        /// </summary>
        /// <returns>gateways in the format of [gatewayname][version].Gateway ie ibsgateway712.Gateway</returns>
        private static List<string> GetRegisteredGateways()
        {
            var keys = Registry.ClassesRoot.GetSubKeyNames().Where(x => x.StartsWith("ibsgateway",
            StringComparison.InvariantCultureIgnoreCase));
            return keys.ToList();
        }
        public static string GetLatestRegisteredGateway()
        {
            string result = string.Empty;
            // Get all the registered gateways from the registry
            List<string> registeredGateways = GetRegisteredGateways();
            // Create the dictionary for holding the registered gateway versions
            Dictionary<int, string> versions = new Dictionary<int, string>();
            // Loop each of the registered entries
            foreach (string registeredGateway in registeredGateways)
            {
                // Break up the gateway name into an array
                // Ie. gwArr[0] = infusiongatewayxxx
                // gwArr[1] = Gateway
                string[] gwArr = registeredGateway.Split('.'); // Ensure the string was valid and has split ok
                if (gwArr.Count() > 0)
                {
                    // Convert to upper case and split on "IBSGATEWAY" portion
                    // This will leave the version number
                    string[] versionNumArr = gwArr[0].ToUpper().Split(new string[] { "IBSGATEWAY" }
                    , StringSplitOptions.RemoveEmptyEntries);
                    // Ensure the version number arr is populated
                    if (versionNumArr.Count() > 0)
                    {
                        int versionNum = 0;
                        // Try to parse the string as an integer

                        if (int.TryParse(versionNumArr[0], out versionNum))
                        {
                            // Add the to list of available version if it does not already exist and the original gateway class name
                            if (!versions.ContainsKey(versionNum))
                            {
                                versions.Add(versionNum, registeredGateway);
                            }
                        }
                    }
                }
            }
            // Check the versions list is populated
            if (versions.Count > 0)
            {
                // Order by the highest version and set the result to that value
                result = versions.OrderByDescending(x => x.Key).FirstOrDefault().Value;
            }
            // Return the latest gateway version class name
            return result;
        }
    }
}