im creating to-do list without any tutorial and i stucked when i tried to code clear button. I have a problem because this code removing only half of 'li' items in my list. I checked length of document.querySelectorAll('li) and it return correct value of list length , and i think in each loop execution i delete first element because document.querySelector('li) return only first element. Could you help me? And another question : Is somewhere in web program that can i see step by step exection of my code with DOM? I found few sites but there i can only debug code without html and css.
There is my code:
let clear = document.querySelector('.clear');
let input = document.querySelector('.input');
let submit = document.querySelector('.submit');
let list = document.querySelector('.list');
submit.addEventListener('click', function() {
const el = document.createElement('li');
list.appendChild(el);
let items = document.querySelectorAll('li');
for (i = 0; i < items.length; i++) {
items[items.length - 1].textContent = input.value;
}
});
clear.addEventListener('click', function() {
console.log(document.querySelectorAll('li').length);
for (i = 0; i < document.querySelectorAll('li').length; i++)
list.removeChild(document.querySelector('li'));
console.log(list);
});* {
margin: 0;
padding: 0;
box-sizing: border-box;
}
body {
display: flex;
justify-content: flex-start;
align-items: center;
flex-direction: column;
max-height: 100vh;
max-width: 90vw;
}
h1 {
text-align: center;
}
.wrap {
padding: 50px;
border: 2px solid black;
border-radius: 20%;
background-color: red;
}
.list {
width: 100%;
margin-left: 100px;
font-size: 2rem;
font-weight: bold;
}<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta http-equiv="X-UA-Compatible" content="IE=edge" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Document</title>
<link rel="stylesheet" href="style.css" />
</head>
<body>
<div class="wrap">
<h1>To do list</h1>
<input type="text" placeholder="Add an item!" class="input" />
<button class="submit">Submit</button>
<button class="clear">Clear List</button>
</div>
<ol class="list"></ol>
<script src="script.js"></script>
</body>
</html>In your case, your loop was calculating its length each time of the loop while i was still incrementing
I you had two elements, it would have deleted the first item, then at the second loop, the list would have a length of 1 and i would be equals to 1 so the loop would break
You can use a for of loop instead of a for i loop and remove the child by reference
clear.addEventListener('click', function() {
const childs = document.querySelectorAll('li')
for (const child of childs){
list.removeChild(child)
}
});
Note : this can also be done using a for i loop if you instantiate the list
clear.addEventListener('click', function() {
const childs = document.querySelectorAll('li')
for (let i = 0; i < childs.length; i++){
list.removeChild(childs[i])
}
});
I invent a new way to solve it
clear.addEventListener('click', function () {
for (i = 0; i < document.querySelectorAll('li').length + i; i++)
list.removeChild(document.querySelector('li'));
console.log(list);
});
In each iteration I add 'i' . So i update length