ES6实现的遍历目录函数示例

// npm init
// npm install koa --save-dev
// node --harmony app.js
const fs = require('fs');
var eachDir = (() => {
  let queue = [];
  var eachFiles = (options) => {
    if (queue.length) {
      let path = queue.shift();
      fs.readdir(path, (err, files) => {
        if (err) {
          options.fail(err);
          return;
        }
        files.forEach((file, i) => {
          let url = path + '/' + file;
          let stats = fs.statSync(url);
          if (stats.isDirectory()) {
            queue.push(url);
          } else {
            options.callback && options.callback.call(stats, {
              name: file,
              size: stats.size,
              path: url
            });
          }
        });
        eachFiles(options);
      });
    } else {
      options.done();
    }
  };
  return (path, options) => {
    let stats = fs.statSync(path);
    if (stats.isDirectory()) {
      queue.push(path);
    }
    eachFiles(options);
  };
})();
let total = 0, fileTypes = {};
eachDir('./', {
  callback(file) {
    let ret = file.name.match(/\.(\w+$)/);
    if (ret) {
      if (!fileTypes[ret[0]]) {
        fileTypes[ret[0]] = 0;
      }
      fileTypes[ret[0]] += 1;
    }
    // console.log(file);
    total++;
  },
  done() {
    console.log(total, fileTypes);
    fs.writeFile('./result.txt', JSON.stringify(fileTypes), (err) => {
      if (err) throw err;
      console.log('done');
    });
  },
  fail(err) {
    console.log(err);
  }
});