vs循环引用(c#)

class Foo
{
    private WeakReference<Bar> _barRef;

    public Foo()
    {
        _barRef = new WeakReference<Bar>(new Bar(this));
    }

    public void DoSomething()
    {
        if (_barRef.TryGetTarget(out var bar))
        {
            bar.DoSomething();
        }
    }
}

class Bar
{
    private WeakReference<Foo> _fooRef;

    public Bar(Foo foo)
    {
        _fooRef = new WeakReference<Foo>(foo);
    }

    public void DoSomething()
    {
        if (_fooRef.TryGetTarget(out var foo))
        {
            // Do something with foo
        }
    }
}