Business
Jobs
  • About Us
  • Solutions
    • Job Postings
      Post your job and receive qualified candidates in 48h.
    • Candidate Assessments
      500+ technical and psychological tests, plus anti-fraud.
    • Headhunting
      Tailor-made executive search from start to finish.
    • Payroll + EOR
      Payroll dispersal and EOR across 15+ LATAM countries.
  • Pricing
  • Jobs

0

83
Views
Update quantity of items in cart without pushing entirety of object in JS

I'm having a bit of trouble with this problem. I'm working on the project of an e-commerce application that works on several html pages. I managed to push products through the cart html page, but I can't seem to find a way to update on this page only the quantity of a product and not push every elements of said product (images, id, etc). Onclick, if product exists, I only want quantity to be updated. Here's the code if any of you can help me out that'd be greatly appreciated.

setItems(kanap);

function setItems(kanap) {

  let cart = JSON.parse(localStorage.getItem('cart'));

  let imgKanap = kanap.imageUrl;
  let idKanap = kanap._id;
  let colorKanap = colors.value;
  let quantityKanap = parseInt(quantity.value);
  let key = idKanap + ' ' + colorKanap;

  let cartItem = {
    id: idKanap,
    color: colorKanap,
    quantity: quantityKanap,
    kanap: kanap
  };

  if (cart === null) {
    cart = [];
  }

  cart.push(cartItem);

  localStorage.setItem('cart', JSON.stringify(cart));

  function addProduct(cartItem) {
    var found = false;
    for (key in cartItem) {
      if (cartItem[key].idKanap == idKanap) {
        cartItem[key].quantityKanap += quantityKanap;
        found = true;
        break;
      }
    }
    if (!found) {
      cart.push(cartItem);
    }
  }
  addProduct();
}
<div class="item__content__addButton">
  <button id="addToCart" type="submit">Ajouter au panier</button>
</div>

<section class="cart">
  <!-- <section id="cart__items">
         <article class="cart__item" data-id="{product-ID}">
            <div class="cart__item__img">
              <img id ="image" alt="Photographie dun canapé">
            </div>
            <div class="cart__item__content">
              <div class="cart__item__content__titlePrice">
                <h2 class=title></h2>
                <p class =price></p>
              </div>
              <div class="cart__item__content__settings">
                <div class="cart__item__content__settings__quantity">
                  <p class= quantity>Qté : </p>
                  <input type="number" class="itemQuantity" name="itemQuantity" min="1" max="100" value="">
                </div>
                <div class="cart__item__content__settings__delete">
                  <p class="deleteItem">Supprimer</p>
                </div>
              </div>
            </div>
        </article> -->
</section>

about 4 years ago · Juan Pablo Isaza
1 answers
Answer question

0

There's a few approaches you can take, but I am using .find to look through your cart.

If the .find() function finds an item with the same id as you're about to add, it will up the quantity of the existing item instead of appending another object with the same ID.

I used a mock local storage since local storage doesn't work in these snippets so just ignore that and use what you've been doing for local storage access.

let mockLS = null;

// guessed at the structure here, you may have something slightly different
const exampleItem = {
  _id: "abc",
  imageUrl: "imageurlexample",
  colors: {
    value: "red"
  },
  quantity: {
    value: 1
  }
}

const exampleItem2 = {
  _id: "abc2",
  imageUrl: "imageurlexample2",
  colors: {
    value: "blue"
  },
  quantity: {
    value: 1
  }
}

function setItems(kanap) {

  //let cart = JSON.parse(localStorage.getItem('cart'));

  // using a mock localstorage here since it doesn't work within this snippet, use what you currently have instead
  let cart = mockLS;

  let imgKanap = kanap.imageUrl;
  let idKanap = kanap._id;
  let colorKanap = kanap.colors.value;
  let quantityKanap = parseInt(kanap.quantity.value);
  let key = idKanap + ' ' + colorKanap;

  let cartItem = {
    id: idKanap,
    color: colorKanap,
    quantity: quantityKanap
    //kanap: kanap not sure why you want the whole obj here so I left this one out
  };

  if (cart === null) {
    cart = [];
  }

  // here is the case where cart exists and there may be the same item in it
  const itemExists = cart.find(item => {
    if(item.id === idKanap) {
      item.quantity += quantityKanap;
      return true;
    }
    return false;
  })

  if (!itemExists) {
    cart.push(cartItem);
  }

  //localStorage.setItem('cart', JSON.stringify(cart));
  mockLS = cart;
}

setItems(exampleItem);
setItems(exampleItem2);
setItems(exampleItem);

console.log(mockLS)

about 4 years ago · Juan Pablo Isaza Report
Answer question
Find remote jobs

Discover the new way to find a job!

Top jobs
Top job categories
Business
Post vacancy Pricing Sales
Legal
Terms and conditions Privacy policy
© 2026 PeakU Inc. All Rights Reserved.
Andres GPT
Show me some job opportunities
There's an error!