passing void to a generic class

Question

I'm trying to create a form that will animate something while processing a particular task (passed as a delegate to the constructor). It's working fine, but the problem I'm having is that I can't instantiate a copy of my generic class if the particular method that I want to perform has a return type of void.

I understand that this is by design and all, but I'm wondering if there is a known workaround for situations like this.

If it helps at all my windows form looks like so (trimmed for brevity):

public partial class operatingWindow<T> : Form
{
    public delegate T Operation();
    private Operation m_Operation;

    private T m_ReturnValue;
    public T ValueReturned { get { return m_ReturnValue; } }

    public operatingWindow(Operation operation) { /*...*/ }
}

And I call it like:

operatingWindow<int> processing = new operatingWindow<int>(new operatingWindow<int>.Operation(this.doStuff));
processing.ShowDialog();

// ... 
private int doStuff()
{
    Thread.Sleep(3000);

    return 0;
}

Answer 1

No, you'll need to create an overload to do that.

e.g.

  public operatingWindow(Action action) 
  { 
     m_Operation=() => { action(); return null; }
  }

Also you don't need to define your own delegate, you can use Func<T> and Action.