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JavaScript

jason limmm
jason limmm
8,009 Points
Posted by jason limmm
jason limmm
8,009 Points

cannot read properties of undefined

here is my code

products.js

const data = require('../data/products.json');
const products = data.products;

router.get('/', (req, res)=>{
    res.render('productslist');
});

router.get('/:id', (req, res)=>{
    const productname = products[req.params.id].productname;
    const productbio = products[req.params.id].aboutme;
    const productinfo ={productname, productbio};
    res.render('producttemplate', productinfo);
});

producttemplate.pug

extends layout

block content
    h1=productname
    p=productbio

data.json

{
    "data": {
        "title":"products",
        "products":[
            {
                "productname":"aphone 14 pro makintos",
                "aboutme":"i am versatile makapplecomp for the 1941 to now i still been used because of my uh versatile"
            },
            {
                "productname":"phone",
                "aboutme":"idk"
            }
        ]
    }
}

the app says "TypeError: Cannot read properties of undefined (reading '0')"

Rich Donnellan
Rich Donnellan
Treehouse Moderator 27,708 Points
Rich Donnellan
Rich Donnellan
Treehouse Moderator 27,708 Points

Is this from a specific lesson or something else?

I recommend using camelCase for your variables, as it's rather tricky to scan/parse (productName vs. productname).