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JavaScript

Posted by Jason Pallone
Jason Pallone
11,340 Points

why brackets instead of dot here?

const express = require('express');
const router = express.Router();
const data = require('../data/flashcardData.json').data
const cards = data.cards




router.get('/:id', (req, res)=>{
    const cardSide = req.query.cardSide
    const id = req.params.id
    const text = cards[id][cardSide]
    const hint = cards[id].hint

    const templateData = {text, hint}

    res.render('cards', templateData)
})

module.exports= router

const text = cards[id][cardSide] why do we use brackets on cardSide? why wouldn't it be a dot like with hint, since we are searching for the question/answer? Using a query to access a array index is new to me, thanks in advance!

1 Answer

Steven Parker
Steven Parker
243,215 Points
Steven Parker
Steven Parker
243,215 Points

It might look like an array index, but its another way of accessing a property. The dot notation is good when you know the property name in advance. But when the property name is contained in a variable, the bracket notation is the only way to access that property.

Jason Pallone
Jason Pallone
11,340 Points

Ok that makes sense to me, thanks!