1、实现一个文件上传展示

创建目录如下：
image.png

编写index.js代码：

  1. var server = require("./server");
  2. var router = require("./router");
  3. var requestHandlers = require('./requestHandlers')
  5. var handle = {}
  6. handle["/"] = requestHandlers.start;
  7. handle["/start"] = requestHandlers.start;
  8. handle["/upload"] = requestHandlers.upload;
  9. handle["/show"]= requestHandlers.show;
  11. server.start(router.route, handle);

编写requestHandlers.js代码：

  1. var fs = require("fs");
  2. var path = require("path")
  3. var formidable = require("formidable");
  4. const url = path.join(process.cwd(), '/tmp/test.png')
  6. function start(response) {
  7.   var body = '<html>' +
  8.     '<head>' +
  9.     '<meta http-equiv="Content-Type" ' +
  10.     'content="text/html; charset=UTF-8" />' +
  11.     '</head>' +
  12.     '<body>' +
  13.     '<form action="/upload" enctype="multipart/form-data" ' +
  14.     'method="post">' +
  15.     '<input type="file" name="upload">' +
  16.     '<input type="submit" value="Upload file" />' +
  17.     '</form>' +
  18.     '</body>' +
  19.     '</html>';
  21.   response.writeHead(200, { "Content-Type": "text/html" });
  22.   response.write(body);
  23.   response.end();
  24. }
  26. function upload(response, request) {
  27.   var form = new formidable.IncomingForm();
  28.   form.parse(request, function (error, fields, files) {
  29.     fs.renameSync(files.upload.filepath, url);
  30.     response.writeHead(200, { "Content-Type": "text/html" });
  31.     response.write("received image:<br/>");
  32.     response.write("<img src='/show' />");
  33.     response.end();
  34.   });
  35. }
  37. function show(response) {
  38.   fs.readFile(url, "binary", function (error, file) {
  39.     if (error) {
  40.       response.writeHead(500, { "Content-Type": "text/plain" });
  41.       response.write(error + "\n");
  42.       response.end();
  43.     } else {
  44.       response.writeHead(200, { "Content-Type": "image/png" });
  45.       response.write(file, "binary");
  46.       response.end();
  47.     }
  48.   });
  49. }
  51. exports.start = start;
  52. exports.upload = upload;
  53. exports.show = show;

编写router.js代码：

  1. function route(handle, pathname, response, request) {
  2.   if (typeof handle[pathname] === 'function') {
  3.     return handle[pathname](response, request);
  4.   } else {
  5.     response.writeHead(404, { "Content-Type": "text/plain" });
  6.     response.write("404 Not found");
  7.     response.end();
  8.   }
  9. }
  11. exports.route = route;

编写server.js代码：

  1. var http = require("http");
  2. var url = require("url");
  4. function start(route, handle) {
  5.   function onRequest(request, response) {
  6.     var pathname = url.parse(request.url).pathname;
  7.     route(handle, pathname, response, request);
  8.   }
  10.   http.createServer(onRequest).listen(8888, () => {
  11.     console.log("Server has started 8888.");
  12.   });
  13. }
  15. exports.start = start;

运行效果：
image.png
image.png