jQuery.click() vs onClick

Question

I have a huge jQuery application, and I\'m using the below two methods for click events.

First method

HTML

Answer 1

Performance

There are already many good answers here however, authors sometimes mention about performance but actually nobody investigate it yet - so I will focus on this aspect here. Today I perform test on Chrome 83.0, Safari 13.1 and Firefox 77.0 for solutions mention in question and additionally few alternative solutions (some of them was mention in other answers).

Results

I compare here solutions A-H because they operate on elements id. I also show results for solutions which use class (I,J,K) as reference.

• solution based on html-inline handler binding (B) is fast and fastest for Chrome and fastest for small number of elements
• solutions based on getElementById (C,D) are fast, and for big number of elements fastest on Safari and Firefox
• referenced solutions I,J based are fastest for big num of elements so It is worth to consider use class instead id approach in this case
• solution based on jQuery.click (A) is slowest

Details

Actually It was not easy to design performance test for this question. I notice that for all tested solutions, performance of triggering events for 10K div-s was fast and manually I was not able to detect any differences between them (you can run below snippet to check it yourself). So I focus on measure execution time of generate html and bind event handlers for two cases

• 10 divs - you can run test HERE
• 1000 divs - you can run test HERE

// https://stackoverflow.com/questions/12627443/jquery-click-vs-onclick
let a= [...Array(10000)];

function clean() { test.innerHTML = ''; console.clear() }

function divFunction(el) {
  console.log(`clicked on: ${el.id}`);
}

function initA() {
  test.innerHTML = a.map((x,i)=> `
${i}
`).join``;
  a.map((x,i)=> $(`#myDiv${i}`).click(e=> divFunction(e.target)));
}

function initB() {
  test.innerHTML = a.map((x,i)=> `
${i}
`).join``;
}

function initC() {
  test.innerHTML = a.map((x,i)=> `
${i}
`).join``;
  a.map((x,i)=> document.getElementById(`myDiv${i}`).onclick = e=> divFunction(e.target) );
}

function initD() {
  test.innerHTML = a.map((x,i)=> `
${i}
`).join``;
  a.map((x,i)=> document.getElementById(`myDiv${i}`).addEventListener('click', e=> divFunction(e.target) ));
}

function initE() {
  test.innerHTML = a.map((x,i)=> `
${i}
`).join``;
  a.map((x,i)=> document.querySelector(`#myDiv${i}`).onclick = e=> divFunction(e.target) );
}

function initF() {
  test.innerHTML = a.map((x,i)=> `
${i}
`).join``;
  a.map((x,i)=> document.querySelector(`#myDiv${i}`).addEventListener('click', e=> divFunction(e.target) ));
}

function initG() {
  test.innerHTML = a.map((x,i)=> `
${i}
`).join``;
  a.map((x,i)=> window[`myDiv${i}`].onclick = e=> divFunction(e.target) );
}

function initH() {
  test.innerHTML = a.map((x,i)=> `
${i}
`).join``;
  a.map((x,i)=> window[`myDiv${i}`].addEventListener('click',e=> divFunction(e.target)));
}

function initI() {
  test.innerHTML = a.map((x,i)=> `
${i}
`).join``;
  [...document.querySelectorAll(`.box`)].map(el => el.onclick = e=> divFunction(e.target));
}

function initJ() {
  test.innerHTML = a.map((x,i)=> `
${i}
`).join``;
  [...document.querySelectorAll(`.box`)].map(el => el.addEventListener('click', e=> divFunction(e.target)));
}

function initK() {  
  test.innerHTML = a.map((x,i)=> `
${i}
`).join``;
  $(`.box`).click(e=> divFunction(e.target));
}



function measure(f) {  
  console.time("measure "+f.name);
  f();
  console.timeEnd("measure "+f.name)
}

#test {
  display: flex;
  flex-wrap: wrap;
}

.box {
  margin: 1px;
  height: 10px;
  background: red;
  font-size: 10px;
  cursor: pointer;
}

This snippet only presents used solutions. Click to solution button and then click on any red box to trigger its handler
A
B
C
D
E
F
G
H
I
J
K
Clean

Here is example test for Chrome