added command line argument for plc port

.gitignore

@@ -26,6 +26,7 @@ bld/
 
 # Visual Studio 2015/2017 cache/options directory
 .vs/
+.vscode/
 # Uncomment if you have tasks that create the project's static files in wwwroot
 #wwwroot/
 

SoftPlc/Services/PlcService.cs

@@ -3,6 +3,8 @@
 using System.Linq;
 using SoftPlc.Interfaces;
 using SoftPlc.Models;
+using Microsoft.Extensions.Configuration;
+
 
 namespace SoftPlc.Services
 {
@@ -11,11 +13,21 @@ public class PlcService : IPlcService, IDisposable
 		private readonly S7Server server;
 		private readonly bool serverRunning;
 		private readonly Dictionary<int, DatablockDescription> datablocks = new Dictionary<int, DatablockDescription>();
-		public PlcService()
+		public PlcService(IConfiguration configuration)
 		{
 			Console.WriteLine("Initializing plc service...");
 
 			server = new S7Server();
+
+
+			if(configuration.GetChildren().Any(item => item.Key.Equals("plcPort")))
+			{	
+				UInt16 plcPort;
+				var parsed = UInt16.TryParse(configuration["plcPort"], out plcPort);
+				if(parsed)
+					server.SetParam(S7Consts.p_u16_LocalPort, ref plcPort);
+			}
+
 			var error = server.Start();
 			serverRunning = error == 0;
 			if (serverRunning) Console.WriteLine("plc server started!");

SoftPlc/Startup.cs

@@ -28,8 +28,7 @@ public Startup(IConfiguration configuration)
         // This method gets called by the runtime. Use this method to add services to the container.
         public void ConfigureServices(IServiceCollection services)
         {
-	        var plcService = new PlcService();
-			services.AddSingleton<IPlcService>(plcService);
+			services.AddSingleton<IPlcService, PlcService>();
 
 	        // Register the Swagger generator, defining 1 or more Swagger documents
 	        services.AddSwaggerGen(c =>
@@ -81,6 +80,9 @@ public void Configure(IApplicationBuilder app, IHostingEnvironment env)
 	        });
 
 			app.UseMvc();
+
+			//initialize plc service on start
+			var plcService = app.ApplicationServices.GetService<IPlcService>();
         }
     }
 }