A Blue Prism project with custom DLLs: 4 dummies

It seems this blog post was found really interesting from lot of you, but i also read a lot of comments about how can you set up a project and use DLL with BP, so i will show you a practical and really simple example.
Here below the code of the DLL i will use, just two classes:

1. Log Helper: write something in the event viewer (could be useful for bug hunting)
2. Program: the typical entry point for every .NET console application

LogHelper.cs

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using System; using System.Diagnostics;   namespace BP.ExternalDll.Example {     public class LogHelper     {         private readonly string _log;         private readonly string _source;           public LogHelper(string source, string log)         {             _source = source;             _log = log;         }                   public void LogWarning(string message)         {             try             {                 CreateEventSource();                 EventLog.WriteEntry(_source, message, EventLogEntryType.Warning);             }             catch (Exception)             {                 // ignored                 // If you're here, it means you cannot write on event registry             }         }                   private void CreateEventSource()         {             if (!EventLog.SourceExists(_source))             {                 EventLog.CreateEventSource(_source, _log);             }         }     } }

Program.cs

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namespace BP.ExternalDll.Example {     public class Program     {         public static void Log()         {             string currentDirectory = System.Environment.CurrentDirectory;             LogHelper _helper = new LogHelper("BP.ExternalDll.Example", "Test library");             _helper.LogWarning(currentDirectory);         }           static void Main(string[] args)         {             Log();         }     } }

So, compile everything and place your brand new DLL in this folder: C:\Program Files\Blue Prism Limited\Blue Prism Automate .
Don't try to put the file in other folders in your PC or organize the BP folder with subfolders: it will not work and don't argue with me that BP offers this functionality, IT DOESN'T WORK.

I said: IT DOESN'T WORK

I've figured out with Antonio Durante how to overcome this problem but I think i will try this in the next future.
In the code block you just have to write:

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1	Program.Log()

and you will start to find some new rows in your event viewer. It's clear that this is just a little example, you can complicate the things as you wish.
My advice is to create always a BusinessDelegate class that holds all the methods you want to expose and create a single VBO action for every method in the BP, this will enhance testability and maintenance. That's all folks!