我在 app.set 的 app.js 文件中的节点 js 中出现错误

Question

我不知道为什么会出错，但如果您能提供帮助，我将非常感激。

这是我的 app.js代码和重要说明，我通过节点 package 管理器下载了 express 和 body-parser。

const express = require('express');
const bodyParser = require('body-parser');

const app = express;

app.set('view engine', 'ejs');

app.get("/",function(req,res){
    var today = new Date();
    var option = {
        weekday:"long",
        day:"numeric",
        month:"long"
    };
    var day = today.toLocaleDateString("en-US",option);
res.sendfile(__dirname + "/index.html");
res.render('list', {kindOfDay:day});

});
app.listen(3000,function(){
  console.log("Server started on port 3000");
});

我的错误

C:\Users\a\Desktop\Todo-List v1\app.js:6
app.set('view engine', 'ejs');
    ^
TypeError: app.set is not a function
    at Object.<anonymous> (C:\Users\a\Desktop\Todo-List v1\app.js:6:5)
    at Module._compile (internal/modules/cjs/loader.js:1137:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1157:10)
    at Module.load (internal/modules/cjs/loader.js:985:32)
    at Function.Module._load (internal/modules/cjs/loader.js:878:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:71:12)
    at internal/main/run_main_module.js:17:47
[nodemon] app crashed - waiting for file changes before starting...

Answer 1

尝试这个

const app = express();

Answer 2

尝试使用

const app = express();

为了生成express 应用程序，您必须从您的节点调用 express function。

Answer 3

  Loading express module returns a function. So, Please try changing your code like this.
  const app = express();

const express = require('express');
const bodyParser = require('body-parser');

const app = express();

app.set('view engine', 'ejs');

app.get("/",function(req,res){
    var today = new Date();
    var option = {
        weekday:"long",
        day:"numeric",
        month:"long"
    };
    var day = today.toLocaleDateString("en-US",option);
res.sendfile(__dirname + "/index.html");
res.render('list', {kindOfDay:day});

});
app.listen(3000,function(){
  console.log("Server started on port 3000");
});