Question

I am trying to revise my logging library. Here is where I’m stuck. I use an enumeration, let’s call it ActionType, to identify my operations like UserLogin, PurchaseOrder… hundreds of them. And I use this type in my logger methods. But since I am seperating my logger library from my project specific code in the sake of loose coupling and base library can’t access ActionType defined in a project, how can I achieve this. To clarify it let me explain same case in java. Java allows enums to implement interfaces. So I could write:

In base logger library I could define;

public interface IActionType {}

and in one of my several projects

public enum ActionType implements IActionType {UserLogin, PurchaseOrder, .....}

So when I called my logger.log(ActionType.UserLogin, ....) base library would get the underlying action. This would all be suffice. Is there anyway around it to accomplish this in c#? By the way, I considered using IoC containers, but I want something more elegant.

Many thanks for any help…

Answer 1

Here is approach log4net uses for Level class (yes, it is class, not enum):

public class ActionType : IActionType
{
   public static readonly ActionType UserLogin;
   public static readonly ActionType PurchaseOrder;

   static ActionType()
   {
       UserLogin = new ActionType(1, "User Login");
       // ...
   }

   public ActionType(int value, string name)
   {           
       // verify arguments values
       Value = value;
       Name = name;
   }

   public int Value { get; private set; }
   public string Name { get; private set; }
}

And interface

public interface IActionType
{
    int Value { get; }
    string Name { get; }
}

Usage:

logger.Log(ActionType.UserLogin);