I am trying to add an event listener but no result came. I know JavaScript has a hoisting feature but I believe I tried all except the correct solution.
const cbox = document.querySelectorAll(".box");
function doit() {
for (let i = 0; i < cbox.length; i++){
cbox[i].classList.add("red");
}
}
cbox.addEventListener("click", doit, false);
Can somebody spot the mistake I make?
There are some dissimilarities between the code and the link you have provided. There is no function doit()
in there.
You have attached addEvenListener
to the NodeList
in cbox.addEventListener("click",.....
, you have to loop through the list and attach the event to the current element:
Try the following:
const cbox = document.querySelectorAll(".box");
for (let i = 0; i < cbox.length; i++) {
cbox[i].addEventListener("click", function() {
cbox[i].classList.toggle("red");
});
}
*,
html,
body {
padding: 0;
margin: 0;
}
.box {
width: 10rem;
height: 10rem;
background-color: yellowgreen;
float: left;
position: relative;
margin: 0.5rem;
transition: .5s all;
}
h3 {
display: block;
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
}
.box:not(:first-child) {
margin-left: 1rem;
}
.red {
background-color: orangered;
}
<div id="box1" class="box box1">
<h3>Box 1</h3>
</div>
<div id="box2" class="box box2">
<h3>Box 2</h3>
</div>
<div id="box3" class="box box3">
<h3>Box 3</h3>
</div>
<div id="box4" class="box box4">
<h3>Box 4</h3>
</div>
You can also use Array.prototype.forEach()
with arrow function
syntax that will allow you to achieve the same with less code:
let cbox = document.querySelectorAll(".box");
cbox.forEach(box => {
box.addEventListener('click', () => box.classList.toggle("red"));
});
*,
html,
body {
padding: 0;
margin: 0;
}
.box {
width: 10rem;
height: 10rem;
background-color: yellowgreen;
float: left;
position: relative;
margin: 0.5rem;
transition: .5s all;
}
h3 {
display: block;
position: absolute;
top: 50%;
left: 50%;
transform: translate(-50%, -50%);
}
.box:not(:first-child) {
margin-left: 1rem;
}
.red {
background-color: orangered;
}
<div id="box1" class="box box1">
<h3>Box 1</h3>
</div>
<div id="box2" class="box box2">
<h3>Box 2</h3>
</div>
<div id="box3" class="box box3">
<h3>Box 3</h3>
</div>
<div id="box4" class="box box4">
<h3>Box 4</h3>
</div>