TypeError:无法读取未定义的属性'handle' – if(fn.handle && fn.set)mount_app = fn

我希望能得到一些帮助。 不确定这意味着什么,因为这是我第一次使用节点和expression。 我设置了快递和节点一起使用,并试着按照站点上的信息Express.js 。 希望有一些帮助理解我可能会错过这里请。

...\node_modules\express\lib\application.js:178 if (fn.handle && fn.set) mount_app = fn; ^ TypeError: Cannot read property 'handle' of undefined at Function.app.use (....\node_modules\express\lib\application.js:178:9) at Object.<anonymous> (....\app.js:18:5) at Module._compile (module.js:456:26) at Object.Module._extensions..js (module.js:474:10) at Module.load (module.js:356:32) at Function.Module._load (module.js:312:12) at Function.Module.runMain (module.js:497:10) at startup (node.js:119:16) at node.js:906:3

 /** * Module dependencies. */ var http = require('http'); //var express = require('../..'); var module = require("module") var logger = require('morgan'); var express = require('express'); var app = module.exports = express(); var silent = 'test' == process.env.NODE_ENV; var httpServer = http.createServer(app); var bodyParser = require('body-parser'); var methodOverride = require('method-override'); // app middleware app.use(express.static(__dirname + '/public')); app.use(bodyParser()); app.use(methodOverride()); app.use(logErrors); app.use(clientErrorHandler); app.use(errorHandler); api.use(logger('dev')); api.use(bodyParser()); /** * CORS support. */ api.all('*', function(req, res, next) { if (!req.get('Origin')) return next();// use "*" here to accept any origin res.set('Access-Control-Allow-Origin', 'http://localhost:3000'); res.set('Access-Control-Allow-Methods', 'GET, POST'); res.set('Access-Control-Allow-Headers', 'X-Requested-With, Content-Type'); res.set('Access-Control-Allow-Max-Age', 3600); if ('OPTIONS' == req.method) return res.send(200); next(); }); // middleware with an arity of 4 are considered error handling middleware. When you next(err) // it will be passed through the defined middleware in order, but ONLY those with an arity of 4, ignoring regular middleware. var clientErrorHandler=function(err, req, res, next) { if (req.xhr) {// whatever you want here, feel free to populate properties on `err` to treat it differently in here. res.send(err.status || 500, { error: err.message }); } else { next(err);} }; // create an error with .status. we can then use the property in our custom error handler (Connect repects this prop as well) var error=function (status, msg) { var err = new Error(msg); err.status = status; return err; }; var logErrors=function (err, req, res, next) { console.error(err.stack); next(err); }; var errorHandler=function (err, req, res, next) { res.status(500); res.render('error', { error: err }); }; // general config app.set('views', __dirname + '/views'); //app.set('view engine', 'jade'); // our custom "verbose errors" setting which we can use in the templates via settings['verbose errors'] app.enable('verbose errors');// disable them in production use $ NODE_ENV=production node examples/error-pages if ('production' == app.settings.env) {app.disable('verbose errors');} silent || app.use(logger('dev')); // Routes app.get('/404', function(req, res, next){ next();// trigger a 404 since no other middleware will match /404 after this one, and we're not responding here }); app.get('/403', function(req, res, next){// trigger a 403 error var err = new Error('not allowed!'); err.status = 403; next(err); }); app.get('/500', function(req, res, next){// trigger a generic (500) error next(new Error('keyboard cat!')); }); // Error handlers // Since this is the last non-error-handling middleware use()d, we assume 404, as nothing else responded. // $ curl http://localhost:3000/notfound // $ curl http://localhost:3000/notfound -H "Accept: application/json" // $ curl http://localhost:3000/notfound -H "Accept: text/plain" app.use(function(req, res, next){ res.status(404); if (req.accepts('html')) {// respond with html page res.render('404', { url: req.url }); return; } if (req.accepts('json')) {// respond with json res.send({ error: 'Not found' }); return; } res.type('txt').send('Not found');// default to plain-text. send() }); // error-handling middleware, take the same form as regular middleware, however they require an // arity of 4, aka the signature (err, req, res, next).when connect has an error, it will invoke ONLY error-handling middleware. // If we were to next() here any remaining non-error-handling middleware would then be executed, or if we next(err) to // continue passing the error, only error-handling middleware would remain being executed, however here // we simply respond with an error page. app.use(function(err, req, res, next){ // we may use properties of the error object here and next(err) appropriately, or if we possibly recovered from the error, simply next(). res.status(err.status || 500); res.render('500', { error: err }); }); if (!module.parent) {// assigning to exports will not modify module, must use module.exports app.listen(3000); silent || console.log('Express started on port 3000'); }; 


网上收集的解决方案 "TypeError:无法读取未定义的属性'handle' – if(fn.handle && fn.set)mount_app = fn"

问题是你正试图use()一个尚未定义的variables。 如果你使用function logErrors(err, req, res, next) {语法代替var logErrors=function (err, req, res, next) { ,你的types错误应该消失。

在调用app.use之前,尝试移动var clientErrorHandler,errorHandler等。


 var errorHandler = function (req, res, next) { .... } app.use(errorHandler); 





唉! 小小的错别字。