当我尝试渲染 EJS 页面时，我不断收到类型错误...，有人可以看看吗？

Question

Here is the index.js code这是 index.js 代码

    enter code here
    CODE
    const express = require('express');
    const app = express();
    const path = require('path');

    app.use(express.urlencoded({ extended: true }))enter code here // for parsing application/x- 
    www-form-urlencoded
    app.use(express.json()) // for parsing application/json
    app.set('views', path.join(__dirname, 'views'))
    app.set('view engine','ejs')

    const comments = [
        { 
            id:1,
            username: 'tom',
            comment: 'lol'
        },
        {
            id:2,
            username: 'joy',
            comment : 'lmao'
        },
        {
            id:3,
            username: 'ango',
            comment: 'lwkm'
        },
        {
            id:4,
            username: 'shaiyen',
            comment: 'leemao'
        }
    ]

    app.get('/comments',(req,res) => {
        res.render('comments/index',{comments})
    })
 
    app.get('/comments/new', (req,res) =>{
        res.render('comments/new')
    })

    app.post('/comments',(req,res) =>{
        const {username,comment} = req.body;
        comments.push({username,comment})
        res.redirect('/comments');
    })

    app.get('/comments/:id',(req,res) =>{
        const{id}= req.params;
        const comment = comments.find(c => c.id === parseInt(id));
        res.render('comments/show',{comment})
    })

    app.get('/tacos',(req,res) => {
        res.send("GET /tacos response")
    })

    app.post('/tacos', (req,res) =>{
        const  {meat, qty} = req.body;
        res.send(` here are your ${meat} and ${qty} tacos`)
    })

    app.listen(3000, () => {
        console.log("listening on port 3000")
    })

While here is the html file虽然这里是 html 文件

HTML
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Show</title>
</head>
<body>
    <h1>Your comment<%= comment.id %> </h1>
    <h2><%= comment.comment - comment.username %> </h2>
</body>
</html>

It keeps showing this error[TypeError: C:\Users\BARINE\Downloads\game\stuff\getpost\views\comments\show.ejs:10 8|它一直显示此错误[TypeError: C:\Users\BARINE\Downloads\game\stuff\getpost\views\comments\show.ejs:10 8|

9| <body>

10| 10|

<%= comment.id %> <%= 评论.id %>

11|     <h2><%= comment.comment - comment.username %> </h2>

12| </body>

13| </html>

Cannot read properties of undefined (reading 'id') at eval ("C:\Users\BARINE\Downloads\game\stuff\getpost\views\comments\show.ejs":12:34) at show (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\ejs\lib\ejs.js:703:17) at tryHandleCache (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\ejs\lib\ejs.js:274:36) at View.exports.renderFile [as engine] (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\ejs\lib\ejs.js:491:10) at View.render (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\express\lib\view.js:135:8) at tryRender (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\express\lib\application.js:657:10) at Function.render (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\express\lib\application.js:609:3) at ServerResponse.render (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\express\lib\response.js:1039:7) at C:\Users\BARINE\Downloads\game\stuff\getpost\index.js无法在显示 (C:\Users \BARINE\Downloads\game\stuff\getpost\node_modules\ejs\lib\ejs.js:703:17) 在 tryHandleCache (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\ejs\lib\ejs .js:274:36) 在 View.exports.renderFile [作为引擎] (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\ejs\lib\ejs.js:491:10) 在 View。在 tryRender (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules 渲染 (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\express\lib\view.js:135:8) \express\lib\application.js:657:10) 在 Function.render (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\express\lib\application.js:609:3) 在 ServerResponse。渲染 (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\express\lib\response.js:1039:7) 在 C:\Users\BARINE\Downloads\game\stuff\getpost\index.js :50:9 at Layer.handle [as handle_request] (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\express\lib\router\layer.js:95:5)] 1 :50:9 在 Layer.handle [as handle_request] (C:\Users\BARINE\Downloads\game\stuff\getpost\node_modules\express\lib\router\layer.js:95:5)] 1

Answer 1

Hey So I Just Ran Your Code And Everything Seems to be in order嘿，所以我刚刚运行了您的代码，一切似乎都井井有条

Now This Error Which You Got现在你得到的这个错误

Cannot read property 'id' of undefined
    at eval

Is Beacuse the parameter you passing as id don't exist in the comments array是因为您作为id传递的参数在comments数组中不存在

So when this route is called所以当这条路线被调用时

const comment = comments.find(c => c.id === parseInt(id)); //comment == undefined

and thou the error and Ejs compile throw an eval error你的错误和 Ejs 编译抛出一个 eval 错误

Since you new try using try and catch由于您新尝试使用 try and catch

so your code should be like所以你的代码应该像

app.get('/comments/:id',(req,res) =>{
   try{
    const{id}= req.params;
    const comment = comments.find(c => c.id === parseInt(id));
    if(comment){
      res.render('comments/show',{comment})
    }else{
      res.status(404).send("Resource Not Found")
     }
    }catch (err){
      // How you would like to handle your error 
    }
})

当我尝试渲染 EJS 页面时，我不断收到类型错误...，有人可以看看吗？

问题描述

<%= comment.id %> <%= 评论.id %>

1 个解决方案

解决方案1
0 2022-08-19 02:59:08

当我尝试渲染 EJS 页面时，我不断收到类型错误...，有人可以看看吗？

问题描述

<%= comment.id %> <%= 评论.id %>

1 个解决方案

解决方案1 0 2022-08-19 02:59:08

解决方案1
0 2022-08-19 02:59:08