DOM & Events — Series 2

Preview — 3 of 10 questions

What is logged?

javascript

document.body.innerHTML = `
  <button class="btn">A</button>
  <button class="btn">B</button>
  <button class="btn">C</button>
`;

const buttons = document.querySelectorAll('.btn');
console.log(buttons.length);
console.log(Array.isArray(buttons));
console.log(typeof buttons.forEach);

A3, true, "function"

B3, false, "function"

C3, false, "undefined"

D0, false, "function"

What is logged?

javascript

const btn = document.createElement('button');
const log = [];

btn.addEventListener('click', () => log.push('handler 1'));
btn.addEventListener('click', () => log.push('handler 2'));

btn.click();
console.log(log);

A["handler 2"]

B[]

C["handler 1", "handler 2"]

D["handler 1"]

What is logged?

javascript

document.body.innerHTML = `<div id="outer"><button id="inner">Click</button></div>`;

const outer = document.getElementById('outer');

outer.addEventListener('click', (e) => {
  console.log(e.target.id);
  console.log(e.currentTarget.id);
});

document.getElementById('inner').click();

A"outer", "outer"

B"inner", "inner"

C"outer", "inner"

D"inner", "outer"

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