Disposers done right.

IAmDisposable.cs

class IAmDisposable : IDisposable
{
    private int _isDisposed;
    private SomeDisposableThing _disposable1;
    private SomeDisposableBar _disposable2;
    private SomeDisposableBaz _disposable3;

    // Only if you **need** it. You don't though, use SafeHandle.
    //~IAmDisposable()
    //{
    //    if (Interlocked.Exchange(ref _isDisposed, 1) == 0)
    //    {
    //        // NB: Do error handling.
    //        Dispose(false);
    //    }
    //}
        
    public void Dispose()
    {
        if (Interlocked.Exchange(ref _isDisposed, 1) == 0)
        {
            // NB: NO error handling here, users should know about any
            // exceptions coming a from a Dispose() call.
            GC.SuppressFinalize(this);
            Dispose(true);
        }
    }

    private void Dispose(bool disposing)
    {
        if (disposing)
        {
            // You technically don't need to interlocked the fields here,
            // but meh, it's less code.
            IDisposable tmp = Interlocked.Exchange(ref _disposable1, null);
            if (tmp != null) tmp.Dispose();
            tmp = Interlocked.Exchange(ref _disposable2, null);
            if (tmp != null) tmp.Dispose();
            tmp = Interlocked.Exchange(ref _disposable3, null);
            if (tmp != null) tmp.Dispose();
        }
    }
}