Dependency injection

di-1.cs

public class Worker
{
   ILogger _logger;

   public Worker()
   {
      //dependency inversion take #1
      var logFactory = new LogFactory();
      _logger = logFactory.CreateLog();
   }
}

di-2.cs

public class Worker
{
   ILogger _logger;

   public Worker(ILogger logger)
   {
      //dependency inversion by using DI take #2
      _logger = _logger;
   }
}

nodi.cs

public class Worker
{
   ILogger _logger;

   public Worker()
   {
      _logger = new ConsoleLogger();
   }
}