//一个文件上传示例:
(1),建立“server.js”
//复制代码 代码如下:
var http = require('http');
var url = require('url');
function start(route, handler) {
//http服务回调
//request 请求对象
//response 响应对象
//handler 传入的对象,这个对象包含 很多函数对象
function onRequest (request, response) {
//得到请求对象的 url 路径
var pathname = url.parse(request.url).pathname;
// 路由到相应的业务逻辑
route (pathname, handler, response, request);
}
//创建http服务器
http.createServer(onRequest).listen(3000);
console.log('server is starting');
}
exports.start = start
(2),建立“route.js”
//复制代码 代码如下:
function route (pathname, handler, response, request) {
console.log('about to route a request for ' + pathname);
if (typeof handler[pathname] === 'function') {
return handler[pathname](response, request);
} else {
console.log('no request handler found for ' + pathname);
response.writeHead(404, {'Content-Type': 'text/html'});
response.write('404 Not Found!');
response.end();
}
}
exports.route = route;
(3),建立“requestHandler.js”
//复制代码 代码如下:
var querystring = require('querystring'),
fs = require('fs'),
formidable = require('formidable');
function start (response, request) {
console.log('start module');
var body = '<html>'+
'<head>'+
'<meta http-equiv="Content-Type" '+
'content="text/html; charset=UTF-8" />'+
'</head>'+
'<body>'+
'<form action="/upload" enctype="multipart/form-data" method="post">'+
'<input type="file" name="upload" multiple="multiple">'+
'<input type="submit" value="Submit text" />'+
'</form>'+
'</body>'+
'</html>';
// 200代表状态成功, 文档类型是给浏览器识别用的
response.writeHead(200, {'Content-Type': 'text/html'});
//响应对象写入 body (也就是html代码)
response.write(body);
response.end();//写入完毕
}
function upload (response, request) {
console.log('upload module');
var form = new formidable.IncomingForm();
//第二个参数也是一个回调函数, 通过事件触发调用
form.parse(request, function (error, fields, files) {
//files.upload.path 正在写入此文件的 路径。
//Error: EXDEV, cross-device link not permitted
// 'C:\Users\LI~1\AppData\Local\Temp\upload_58c5fbc8c804174256ce2826d766bb0a'
//fs.renameSync(files.upload.path, '/tmp/test.png');
//-------this is old code begin----------------------------------
//util.pump is deprecated. 使用is.pipe(os),然后监听输出流上的“end”事件。
// var utills = require('util');
//
// //把fs.renameSync();,替换成下面的就可以了。
// var readStream = fs.createReadStream(files.upload.path);
// var writeSream = fs.createWriteStream("/tmp/test.png");
// utills.pump(readStream,writeSream,function(){
// fs.unlinkSync(files.upload.path);
// });
//-------this is old code begin----------------------------------
//-----------------------------------------
//在Node.js 我如何移动文件a(files.upload.path)到不同的分区或设备?
var fs = require('fs');
//var util = require('util');
var is = fs.createReadStream(files.upload.path);
var os = fs.createWriteStream("/tmp/test.png");
//在跨不同分区移动文件时,需要复制和取消链接。
is.pipe(os);
is.on('end',function() {
fs.unlinkSync(files.upload.path);
});
/* node.js 0.6 and earlier you can use util.pump:
util.pump(is, os, function() {
fs.unlinkSync('source_file');
});
*/
//-----------------------------------------
//fs.renameSync('I:\\\\tmp1\\\\886.png', '/tmp/test.png');
response.writeHead(200, {'Content-Type': 'text/html'});
response.write('You\'ve sent: <br />');
response.write('<img src="/show" />');
response.end();
});
}
function show (response, request) {
console.log('show module');
fs.readFile ('/tmp/test.png', 'binary', function (error, file) {
if (error) {
response.writeHead(200, {'Content-Type': 'text/html'});
response.write(error);
response.end();
} else {
response.writeHead(200, {'Content-Type': 'image/png'});
response.write(file, 'binary');
response.end();
}
});
}
exports.start = start;
exports.upload = upload;
exports.show= show;
(4),建立“index.js”
//一个文件上传示例:
//复制代码 代码如下:
var server = require('./server');
var router = require('./route');
var requestHandler = require('./requestHandler');
var formidable = require('formidable'); // require路径搜索算法??
var handler = {};
handler['/'] = requestHandler.start;
handler['/start'] = requestHandler.start;
handler['/upload'] = requestHandler.upload;
handler['/show'] = requestHandler.show;
server.start(router.route, handler);
// 四,总结一下
//
// (1),理解 "Fs与Stream之间的联系" 。
// (2),熟练使用 "FS" 相关的api。
// (3),注意细节的把控,比如: 文件操作api同步方式与异步方式之间的处理细节。
// (4),最后强调:理解文件上传例子中的代码组织方式,不断重构,不断总结。