Singleton component design problem

[leppie]

Hi This one has me completely confused. What is the correct way of doing this? I have some "rules" I want to stick with. - Designer support - Object must be a singleton Now these 2 are conflicting :| Here's my possible solution:

public class Singleton : Component
{
private static SingletonInternal instance = null;
private static int instancecount = 0;

private class SingletonInternal : IDisposable
{
//just the normal "instance" implementation

  public void SomeMethod()
  {
  }

  public void Dispose()
  {
     // free unmanaged resources
  }

}

public Singleton()
{
if (instance == null)
instance = new SingletonInternal();
instancecount++;
}

public void SomeMethod()
{
instance.SomeMethod();
}

protected override void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
// free managed resources
}
instancecount--;
if (instancecount == 0)
instance.Dispose();

     this.disposed = true;
  }

}
}

Is this the way to go? All comments welcome :) Cheers MyDUMeter: a .NET DUMeter clone
"Thats like saying "hahahaha he doesnt know the difference between a cyberneticradioactivenuclothermolopticdimswitch and a biocontainingspherogramotron", but with words you have really never heard of."

[pete mcquain]

I think you want something along these lines... public class Singleton : Component { private Singleton m_instance = null; private Singleton(){} // constructor is private so it can't be created externally public static Instance() { if(!m_instance) m_instance = new Singleton; return m_instance; } } Your instance counting and dispose logic should still work. To use it, you dont create a new Singleton, but rather use Singleton s = Singleton.Instance();. -pete

[leppie]

pete mcquain wrote: private Singleton(){} // constructor is private so it can't be created externally That is where it wont work in a designer... MyDUMeter: a .NET DUMeter clone
"Thats like saying "hahahaha he doesnt know the difference between a cyberneticradioactivenuclothermolopticdimswitch and a biocontainingspherogramotron", but with words you have really never heard of."