运行服务器通过节点和 express 出错

Question

我在后端仍然是新手，但从昨天开始，每当我尝试运行我的服务器时，我都会遇到错误。下面是我的代码和错误

 const express = require("express");
const app = express();

PORT = 8443;

app.listen("PORT", () => {
    console.log("Server up and running")
});

这是我的错误

    events.js:288
      throw er; // Unhandled 'error' event
      ^

Error: listen EACCES: permission denied PORT
←[90m    at Server.setupListenHandle [as _listen2] (net.js:1292:21)←[39m
←[90m    at listenInCluster (net.js:1357:12)←[39m
←[90m    at Server.listen (net.js:1456:5)←[39m
    at Function.listen (C:\Users\AbTorres9\Desktop\YelpCamp\node_modules\←[4mexpress←[24m\lib\application.js:618:24)
    at Object.<anonymous> (C:\Users\AbTorres9\Desktop\YelpCamp\app.js:6:5)
←[90m    at Module._compile (internal/modules/cjs/loader.js:1158:30)←[39m
←[90m    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1178:10)←[39m
←[90m    at Module.load (internal/modules/cjs/loader.js:1002:32)←[39m
←[90m    at Function.Module._load (internal/modules/cjs/loader.js:901:14)←[39m
←[90m    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:74:12)←[39m
Emitted 'error' event on Server instance at:
←[90m    at emitErrorNT (net.js:1336:8)←[39m
←[90m    at processTicksAndRejections (internal/process/task_queues.js:84:21)←[39m {
  code: ←[32m'EACCES'←[39m,
  errno: ←[32m'EACCES'←[39m,
  syscall: ←[32m'listen'←[39m,
  address: ←[32m'PORT'←[39m,
  port: ←[33m-1←[39m
}
[nodemon] app crashed - waiting for file changes before starting...

Answer 1

@Abhishek，我认为您使用的端口被您的环境阻止了，请在防火墙上允许它，或者只是禁用防火墙并再次访问它适合您！

Answer 2

您应该在 app.listen() 函数中使用变量而不是 字符串 。尝试使用这样的东西：

app.listen(PORT, () => {
    console.log("Server up and running")
});

Answer 3

您缺少视图正常 JavaScript 的东西。就像定义 port。 .listen 函数接受端口变量而不是字符串 "PORT" 查看工作示例：

const express = require('express');
const app = express();
const port = 8443;

app.listen(port, () => console.log(`Server running on port ${port}!`));

Answer 4

const express = require("express");
const app = express();
const PORT = 8443;
app.listen(PORT, () => {
     console.log("Server up and running")
});

你有一些错误，首先你没有初始化 PORT，其次你在 app.listen()

中将 PORT 作为字符串传递

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运行 服务器通过节点和 express 出错

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运行服务器通过节点和 express 出错