Question

已经回答了类似的问题，但是我还是无法解决自己的错误。

它是使用Express.js的服务器端应用程序。加载主页（http://localhost:3000/index.html）后，每刷新一次〜5次，就会出现错误：

Error: Can't set headers after they are sent.
    at validateHeader (_http_outgoing.js:491:11)
    at ServerResponse.setHeader (_http_outgoing.js:498:3)
    at ServerResponse.header (C:\Users\School\Desktop\Web Technologie\Express\mokershop\node_modules\express\lib\response.js:767:10)
    at ServerResponse.contentType (C:\Users\School\Desktop\Web Technologie\Express\mokershop\node_modules\express\lib\response.js:595:15)
    at ServerResponse.send (C:\Users\School\Desktop\Web Technologie\Express\mokershop\node_modules\express\lib\response.js:145:14)
    at done (C:\Users\School\Desktop\Web Technologie\Express\mokershop\node_modules\express\lib\response.js:1004:10)
    at Object.exports.renderFile (C:\Users\School\Desktop\Web Technologie\Express\mokershop\node_modules\jade\lib\index.js:374:12)
    at View.exports.__express [as engine] (C:\Users\School\Desktop\Web Technologie\Express\mokershop\node_modules\jade\lib\index.js:417:11)
    at View.render (C:\Users\School\Desktop\Web Technologie\Express\mokershop\node_modules\express\lib\view.js:135:8)
    at tryRender (C:\Users\School\Desktop\Web Technologie\Express\mokershop\node_modules\express\lib\application.js:640:10)

所有代码：

var http = require('http');
var url = require('url');
var createError = require('http-errors');
var express = require('express');
var bodyParser = require('body-parser');
var path = require('path');
var serveStatic = require('serve-static');
var cookieParser = require('cookie-parser');
var session = require('express-session');
var SQLiteStone = require('connect-sqlite3')(session);
var fs = require('fs');

var app = express();

// http logger 
var logger = require('morgan');
var accessLogStream = fs.createWriteStream('access.log', { flags: 'a' })
app.use(logger('combined', { stream: accessLogStream }))

// importing db CHECK
var file = 'test.db';
var exists = fs.existsSync(file);
var sqlite3 = require("sqlite3").verbose();
var db = new sqlite3.Database(file);

// session initialisation
var FileStore = require('session-file-store')(session);
app.use(session({
  name: 'server-session-cookie-id',
  secret: 'XXXXXXXX',
  saveUninitialized: true,
  resave: true,
  store: new FileStore()
}));

// making virtual path prefix for static folder CHECK
var staticPath = path.join(__dirname, "static");
app.use(express.static(staticPath));
var publicPath = path.join(__dirname, "public");
app.use(express.static(publicPath));

// view engine setup 
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');
app.use(logger('dev'));
app.use(express.json());
app.use(express.urlencoded({ extended: false }));
app.use(cookieParser());

// catch 404 and forward to error handler 
app.use(function (req, res, next) {
  next(createError(404));
});

// error handler 
app.use(function (err, req, res, next) {
  // set locals, only providing error in development
  res.locals.message = err.message;
  res.locals.error = req.app.get('env') === 'development' ? err : {};

  // render the error page 
  res.status(err.status || 500);
  res.render('error');
});

module.exports = app;

如果有人能指出问题出在哪里，我将不胜感激。

错误：发送后无法设置标头（express.js）

0 个答案: