如何在单击 javascript 后添加 CSS 并在未单击时将其删除

Question

I have encountered a problem with javascript clicking to change CSS

I hope that the outer frame and text of the clicked option can be thickened after clicking, but the ones that are not selected should not be thickened, I have tried several ways of writing, but I still don't know how To complete this requirement, I hope to get everyone's help. thank you

 let plan = document.querySelector('.plan'); let price = document.querySelector('.price'); let item = document.querySelectorAll('.item'); for (var i = 0; i < item.length; i++) { item[i].addEventListener('click', showplan, false); } function showplan(e) { //Originally intended to increase this way, but it seems that it can't be written like this // e.target.closesst('li').classList.add('bold') // e.target.closesst('h2').classList.add('bold') const planSelected = e.target.closest('li').querySelector('h2'); const priceSelected = e.target.closest('li').querySelector('p'); plan.textContent = planSelected.textContent; price.textContent = priceSelected.textContent; }

 @charset "UTF-8";.product＿list { display: flex; }.product＿list.item { border: 1px solid #ccc; border-radius: 6px; text-align: center; padding: 20px; margin: 20px; }.product＿list.item h2 { margin-bottom: 16px; }.product＿list.item:hover { border: 1px solid #222; }.show { border: 2px solid blue; padding: 20px; }.bold { border: 3px solid; font-weight: 900; }

 <ul class="product＿list"> <li class="item"> <h2>coke</h2> <p>$100</p> </li> <li class="item"> <h2>beef</h2> <p>$600</p> </li> </ul> <h2 class="show">Your food of choice is <span class="plan"></span>The total price is<span class="price"></span></h2>

Answer 1

How to add CSS after click through javascript and remove it if not clicked?

Suppose we have a class"item",we want change "h1"

add class:
e.currentTarget.classList.add('item')

remove class:
e.currentTarget.classList.remove('item')

toggle class:
e.currentTarget.classList.toggle('item')

toggle means: (If h1 has this class,remove,if not,add)

Answer 2

You need to toggle the class, you can do that by removing it from every item and only setting it to the selected one:

item.forEach(el => el.classList.remove('active'))
e.currentTarget.classList.add('active')

Also you have a CSS specificity issue:

when using only .bold , the border would be overriden by .product＿list.item

Note, try using currentTarget

 const plan = document.querySelector('.plan'); const price = document.querySelector('.price'); const item = document.querySelectorAll('.item'); function showplan(e) { const target = e.currentTarget; const closestLi = target.closest('li'); const planSelected = closestLi.querySelector('h2'); const priceSelected = closestLi.querySelector('p'); item.forEach(el => el.classList.remove('active')) target.classList.add('active') plan.textContent = planSelected.textContent; price.textContent = priceSelected.textContent; } item.forEach(el => el.addEventListener('click', showplan));

 @charset "UTF-8";.product＿list { display: flex; }.product＿list.item { border: 1px solid #ccc; border-radius: 6px; text-align: center; padding: 20px; margin: 20px; }.product＿list.item h2 { margin-bottom: 16px; }.product＿list.item:hover, { border: 1px solid #222; }.product＿list.active { border: 3px solid red; font-weight: 900; color: red; }.show { border: 2px solid blue; padding: 20px; }

 <ul class="product＿list"> <li class="item"> <h2>coke</h2> <p>$100</p> </li> <li class="item"> <h2>beef</h2> <p>$600</p> </li> </ul> <h2 class="show">Your food of choice is <span class="plan"></span>The total price is<span class="price"></span></h2>

Answer 3

With jQuery, two :radio s and their corresponding label s:

 var $plan = $('.plan'); var $price = $('.price'); var $item = $('.item'); $('.item').on('click', showplan); function showplan(e) { const plan = $(this).find('h2').text(); const price = $(this).find('p').text(); $plan.text(plan); $price.text(price); }

 @charset "UTF-8";.product＿list { display: flex; }.product＿list.item { border: 1px solid #ccc; border-radius: 6px; text-align: center; padding: 20px; margin: 20px; cursor: pointer; }.product＿list input { display: none; }.product＿list.item h2 { margin-bottom: 16px; }.product＿list.item:hover { border: 1px solid #222; }.show { border: 2px solid blue; padding: 20px; }.product＿list input:checked + label { outline: 2px solid black; /* Prevent jumping. */ border: 1px solid black; font-weight: 900; }

 <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> <div class="product＿list"> <input type="radio" name="product" id="coke"> <label class="item" for="coke"> <h2>coke</h2> <p>$100</p> </label> <input type="radio" name="product" id="beef"> <label class="item" for="beef"> <h2>beef</h2> <p>$600</p> </label> </div> <h2 class="show">Your food of choice is <span class="plan">?</span>. The total price is <span class="price">?</span>.</h2>