title: How to close the specified page in flutter
body: <p>Open the app, the page order is A-&gt;B-&gt;C, I want to close the B page on the C page, and the page order is A-&gt;C.
  As far as I know, <code>Navigator.removeRoute(context, routerC)</code> can be used, but I don't know how to get routerC.</p>
  <p>Can you tell me how to do it? thanks</p>