NodeJS – Node Beginner Book – 显示function没有被调用
我正在按照Node Beginner Book中的指南进行操作，并设法完成上一节， 处理file upload 。 本书重点介绍JavaScript调用方法，并在必要时仅使用包含很lessHTML的请求和响应。
我的所有console.log语句都显示了正确的文件path。 但不是显示图像，我得到以下的HTML行：
我认为这个问题是在requestHandlers.js的这一行：
response.write("<img src='/show' />"); 它应该是在requestHandlers.js的底部调用show函数 。 看看这个post底部的控制台输出 ，你可以看到执行不会进入show函数 。 源代码和控制台输出如下：
index.js
var server = require("./server"); var router = require("./router"); var requestHandlers = require("./requestHandlers"); var handle = {}; handle["/"] = requestHandlers.start; handle["/start"] = requestHandlers.start; handle["/upload"] = requestHandlers.upload; handle["/show"] = requestHandlers.show; server.start(router.route, handle);
server.js
var http = require("http"); var url = require("url"); function start(route, handle) { function onRequest(request, response) { var pathname = url.parse(request.url).pathname; console.log("Request for " + pathname + " received."); route(handle, pathname, response, request); } http.createServer(onRequest).listen(8888); console.log("Server has started."); } exports.start = start;
router.js
function route(handle, pathname, response, request) { console.log("About to route a request for " + pathname); if (typeof handle[pathname] === 'function') { handle[pathname](response, request); } else { console.log("No request handler found for " + pathname); response.writeHead(404, {"Content-Type": "text/plain"}); response.write("404 Not found"); response.end(); } } exports.route = route;
requestHandlers.js
var querystring = require("querystring"), fs = require("fs"), formidable = require("formidable"); var path = require('path'); var file = path.join(__dirname, 'tmp', "test.png"); function start(response) { console.log("Request handler 'start' was called."); 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="Upload file"/>'+ '</form>'+ '</body>'+ '</html>'; response.writeHead(200, {"Content-Type": "text/html"}); response.write(body); response.end(); } function upload(response, request) { console.log("Request handler 'upload' was called."); var form = new formidable.IncomingForm(); console.log("about to parse"); form.parse(request, function(error, fields, files) { console.log("parsing done"); console.log("File = "+file); fs.rename(files.upload.path, file, function (error) { if(error) { console.log("error"); fs.unlink(file); console.log(file); fs.rename(files.upload.path, file); console.log(file); } }); response.writeHead(200, {"Content-Type": "text/plain"}); response.write("received image:<br/>"); response.write("<img src='/show' />"); response.end(); }); } function show(response) { console.log("Request handler 'show' was called."); response.writeHead(200, {"Content-Type": "image/png"}); fs.createReadStream(file).pipe(response); } exports.start = start; exports.upload = upload; exports.show = show;
控制台输出
C:\Users\pdl\Projects\TestSeparateJS>node index.js Server has started. Request for / received. About to route a request for / Request handler 'start' was called. Request for /upload received. About to route a request for /upload Request handler 'upload' was called. about to parse parsing done File = C:\Users\pdl\Projects\TestSeparateJS\tmp\test.png error C:\Users\pdl\Projects\TestSeparateJS\tmp\test.png C:\Users\pdl\Projects\TestSeparateJS\tmp\test.png
您将内容作为纯文本而不是HTML发送。 所以浏览器从不像HTML那样运行。 这就是为什么你看到<img>文本而不是<img>标签被生成的原因。
在你的uploadfunction中改变这个：
response.writeHead(200, {"Content-Type": "text/plain"});
对此：
response.writeHead(200, {"Content-Type": "text/html"});