nodejs监控目录

var fs = require('fs');var events = require('events');var util = require('util');function Watcher(watcherDir, processedDir) {    this.watcherDir = watcherDir;    this.processedDir = processedDir;}Watcher.prototype = new events.EventEmitter();Watcher.prototype.watch = function() {    var watcher = this;    fs.readdir(this.watcherDir, function(err, files) {       if (err) throw err;        files.forEach(function(value) {           watcher.emit('process', value);        });    });};Watcher.prototype.start = function() {    var watcher = this;    fs.watchFile(this.watcherDir, function() {        watcher.watch();    });};var watcher = new Watcher('./watcher', './processed');watcher.on('process', function(file) {    var watchFile = this.watcherDir + '/' + file;    var processedFile = this.processedDir + '/' + file.toLowerCase();    fs.rename(watchFile, processedFile, function(err) {        if (err) throw err;    });});watcher.start();