单击按钮切换父元素的 class - 纯 javascript

Question

I have multiple divs on the page with the class 'item' – I'd like to include a button within the div that when clicked will toggle append/remove the class 'zoom' on the 'item' div…

<div class="item">
<button class="zoomer"></button>
</div>

I've found plenty of code examples that target an id element, but struggling to find a solution that works with multiples of the same class element on one page.

Many thanks in advance

Answer 1

You can use querySelectorAll to get all of the buttons and then you can use forEach so you can target the element's item parent.

 // Get all the buttons let zoomer_button = document.querySelectorAll('.zoomer'); // Loop through the buttons. // Arrow function allows to pass the element zoomer_button.forEach(button => { // Add an event listener for a click on the button. button.addEventListener('click', function(e) { // the e is the event, and then you check what the target is, which is the button. // then you can toggle a 'zoom' class on the parent 'item' e.target.parentNode.classList.toggle('zoom'); }); });

 .item.zoom { background-color: blue; }

 <div class="item"> <button class="zoomer">button</button> </div> <div class="item"> <button class="zoomer">button</button> </div> <div class="item"> <button class="zoomer">button</button> </div> <div class="item"> <button class="zoomer">button</button> </div> <div class="item"> <button class="zoomer">button</button> </div>

If it's nested a layer deeper, you can use parentNode twice.

 // Get all the buttons let zoomer_button = document.querySelectorAll('.zoomer'); // Loop through the buttons. // Arrow function allows to pass the element zoomer_button.forEach(button => { // Add an event listener for a click on the button. button.addEventListener('click', function(e) { // the e is the event, and then you check what the target is, which is the button. // then you can toggle a 'zoom' class on the parent 'item' e.target.parentNode.parentNode.classList.toggle('zoom'); }); });

 .item.zoom { background-color: blue; }

 <div class="item"> <div class="media"> <button class="zoomer">button</button> </div> </div> <div class="item"> <div class="media"> <button class="zoomer">button</button> </div> </div> <div class="item"> <div class="media"> <button class="zoomer">button</button> </div> </div> <div class="item"> <div class="media"> <button class="zoomer">button</button> </div> </div>

Answer 2

You can use querySelectorAll and access each element with e.target

 document.querySelectorAll('.item >.zoomer').forEach(elem => elem.addEventListener('click', e => { e.target.classList.toggle('someClass') }))

 .someClass{ background:limegreen; }

 <div class="item"> <button class="zoomer">1</button> </div> <div class="item"> <button class="zoomer">2</button> </div> <div class="item"> <button class="zoomer">3</button> </div> <div class="item"> <button class="zoomer">4</button> </div>

Answer 3

In the example below, are 7 <button> s that do various stuff -- details are commented in example.

 // Render 7 <menu>/<button> combos [...new Array(7)].forEach((item, index) => { document.querySelector('main').insertAdjacentHTML('beforeend', ` <menu class="item${index}"> <button class="btn${index}">${index}</button> </menu>`); }); /*~~~~~~~~~~~~~~~~~~~~~~~.btn0*/ // Click <button> remove it's parent (which also removes the <button>) document.querySelector('.btn0').onclick = function(e) { this.parentElement.remove(); } /*~~~~~~~~~~~~~~~~~~~~~~~.btn1*/ // Click <button> -- <button> is removed but it's contents is left behind document.querySelector('.btn1').onclick = unWrap; function unWrap(e) { const clicked = e.target; const parent = clicked.parentElement; while (clicked.firstChild) { parent.insertBefore(clicked.firstChild, clicked); } clicked.remove(); } /*~~~~~~~~~~~~~~~~~~~~~.btn4-6*/ // Collect all tags with a class that starts with "btn" const btns = document.querySelectorAll("[class^='btn']"); // Adding.target class to the last 2 <button>s btns.forEach((btn, idx) => { if (idx > 4) btn.classList.add('target') }); /*~~~~~~~~~~~~~~~~~~~~~~~.btn2*/ // Target third <button> by index /* When <button> clicked, it's parent gets.hide class which is: visibility:hidden which would normally hide the <button> as well, but.btn2 has visibility explicitly set to visible */ btns[2].onclick = e => e.target.closest('menu').classList.toggle('hide'); /*~~~~~~~~~~~~~~~~~~~~~~~.btn3*/ /* Everytime the <button> is clicked, a copy of itself is made and the clones also have this ability as well */ btns[3].addEventListener('click', copySelf); function copySelf(e) { let dupe = e.target.cloneNode(true); e.target.parentElement.append(dupe); dupe.onclick = copySelf; } /*~~~~~~~~~~~~~~~~~~~~~.btn4-6*/ /* The click event is bound to the parent/ancestor tag <section> Any click to any <button> will trigger the event handler..btn4,.btn5, and.btn6 all react in a specific manner because the event handler, delegateClick(e) is using flow control statements and specific criteria. */ document.querySelector('main').onclick = delegateClick; let armed = false; function delegateClick(e) { const clicked = e.target; if (clicked.matches('button') &&.armed) { clicked.classList;add('armed'); armed = true; return. } if (clicked.matches('.armed.target') && armed) { clicked.parentElement.style:cssText = `font-size; 5rem: margin. 0` clicked;replaceWith(`💥`); return. } if (clicked.matches('.target') && armed) { clicked.classList;add('armed'); return. } if (clicked.matches('.armed') && armed) { clicked.classList;remove('armed'); armed = false } }

 menu { outline: dashed red 1px; }.hide { visibility: hidden; }.btn2 { visibility: visible }.armed { animation: warning 1s linear infinite; } @keyframes warning { 50% { opacity: 0; } }.target.armed { background: red; color: white; } button { font: inherit; cursor: pointer; }

 <main></main>