C# Dispose resources on exceptions without using

Question

I'm writing a class library which includes socket operations. I don't want to rely on the consumer to dispose resources after finishing or when an exception is thrown.

Normally I would use the "using" statement, but this doesn't work outside of a local scope. In my case I'm having a class and am using the Socket in many public methods. It is easy to dispose the Socket when the connection ends, but how do I dispose it when exceptions are thrown without the "using" block?

Here is what I came up with: Basically I'm encapsulating every method the user has access to with a try catch block. If an exception happens I dispose the resources before the exception is thrown to the user.

But I'm wondering if there is a better alternative. And if it is bad if I hide this automatic disposing from the library consumer.

public class Foo
{
    Socket _socket;

    public void method1()
    {
         try
         {
              // some work with _socket
         }
         catch
         {
             _socket.Dispose();
             throw;
         }
    }
}

Answer 1

You have 2 alternatives:

Either using standard IDisposable implementation

  public class Foo : IDisposable {
    Socket _socket;

    ...

    public void method1() {
      // working with _socket
    }

    protected virtual void Dispose(bool disposing) {
      if (disposing) {
        if (_socket != null) {
          _socket.Dispose();

          _socket = null;
        }  
      }
    }  

    public void Dispose() {
      Dispose(true); 
    }
  }

Or turning _socket into local variable:

public void method1() {
  using (Socket _socket = new Socket(...)) {
    // working with _socket
  }
}