Count descendants
중요도: 5
There’s a tree structured as nested ul/li.
Write the code that for each <li> shows:
- What’s the text inside it (without the subtree)
- The number of nested
<li>– all descendants, including the deeply nested ones.
Let’s make a loop over <li>:
for (let li of document.querySelectorAll('li')) {
...
}In the loop we need to get the text inside every li.
We can read the text from the first child node of li, that is the text node:
for (let li of document.querySelectorAll('li')) {
let title = li.firstChild.data;
// title is the text in <li> before any other nodes
}Then we can get the number of descendants as li.getElementsByTagName('li').length.