express搭建的服务器，如何直接在浏览器里面通过url 访问服务器下某个文件夹下的图片这样的静态资源
var constants = require('./constants/event');
var utils = require('util');
var path = require('path')
var fs = require('fs')
var querystring = require('querystring');
var formidable = require('formidable')
var bodyParser = require('body-parser');
var express = require('express')();
var app = require('http').createServer(express);
var io = require('socket.io').listen(app);
var url = require('url');
var User = require('./model/user');
var _ = require('underscore');
var mongoose = require('mongoose');
var port = 3030;
mongoose.connect("mongodb://localhost/imchat");
express.use(bodyParser.json())
express.use(bodyParser.urlencoded({extended:true}))
express.use(require('express').static(path.join(__dirname,"upload")))
这个是我的项目结构，图片都在upload文件夹里面
