watcher.ref()

• 返回：<fs.FSWatcher>

  ¥Returns: <fs.FSWatcher>

调用时，请求只要 <fs.FSWatcher> 处于活动状态，Node.js 事件循环就不会退出。多次调用 watcher.ref() 将不起作用。

¥When called, requests that the Node.js event loop not exit so long as the <fs.FSWatcher> is active. Calling watcher.ref() multiple times will have no effect.

默认情况下，所有 <fs.FSWatcher> 对象都是 "引用的"，因此通常无需调用 watcher.ref()，除非之前已调用 watcher.unref()。

¥By default, all <fs.FSWatcher> objects are "ref'ed", making it normally unnecessary to call watcher.ref() unless watcher.unref() had been called previously.