fsPromises.watch(filename[, options])


    返回异步迭代器,其监视 filename 上的更改,其中 filename 是文件或目录。

    • filename <string> | <Buffer> | <URL>
    • options <string> | <Object>
      • persistent <boolean> Indicates whether the process should continue to run as long as files are being watched. Default: true.
      • recursive <boolean> Indicates whether all subdirectories should be watched, or only the current directory. This applies when a directory is specified, and only on supported platforms (See caveats). Default: false.
      • encoding <string> Specifies the character encoding to be used for the filename passed to the listener. Default: 'utf8'.
      • signal <AbortSignal> An <AbortSignal> used to signal when the watcher should stop.
    • Returns: <AsyncIterator> of objects with the properties:

    Returns an async iterator that watches for changes on filename, where filename is either a file or a directory.

    const { watch } = require('node:fs/promises');
    
    const ac = new AbortController();
    const { signal } = ac;
    setTimeout(() => ac.abort(), 10000);
    
    (async () => {
      try {
        const watcher = watch(__filename, { signal });
        for await (const event of watcher)
          console.log(event);
      } catch (err) {
        if (err.name === 'AbortError')
          return;
        throw err;
      }
    })();

    On most platforms, 'rename' is emitted whenever a filename appears or disappears in the directory.

    All the caveats for fs.watch() also apply to fsPromises.watch().