javascript - How to addEventListener to multiple elements in a single line - Stack Overflow

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Example 1:

element1.addEventListener("input", function() {
  // this function does stuff 
});

Example 2:

element1 && element2.addEventListener("input", function() {
  // this function does stuff
});

It might not be correct grammatically, but is there a way I can give two elements the same event listener at the same time (same line) instead of having to write them apart?

Example 1:

element1.addEventListener("input", function() {
  // this function does stuff 
});

Example 2:

element1 && element2.addEventListener("input", function() {
  // this function does stuff
});

It might not be correct grammatically, but is there a way I can give two elements the same event listener at the same time (same line) instead of having to write them apart?

• javascript
• dom

Share Improve this question Follow edited Nov 4, 2022 at 11:23 JShobbyist 60033 gold badges1010 silver badges2525 bronze badges asked Dec 4, 2016 at 8:13 JamiscoJamisco 1,86233 gold badges1515 silver badges1919 bronze badges 2

• 1 Possible duplicate of Adding event listeners to multiple elements – Meghdad Hadidi Commented Dec 4, 2016 at 8:22
• What if you store it inside array then use each function – RizkiDPrast Commented Dec 4, 2016 at 8:23

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15 Answers 15

Sorted by: Reset to default 191

If you have an array with the elements you could do:

let elementsArray = document.querySelectorAll("whatever");

elementsArray.forEach(function(elem) {
    elem.addEventListener("input", function() {
        // This function does stuff
    });
});

If you don't want to have a separate elementsArray variable defined you could just call forEach from an unnamed array with the two elements.

[ Element1, Element2 ].forEach(function(element) {
   element.addEventListener("input", function() {
      this function does stuff
   });
});

Event Bubbling is the important concept in javascript, so if you can add event on DOM directly, you can save some lines of code, no need for looping :

document.addEventListener('click', function(e){
  if(e.target.tagName=="BUTTON"){
   alert('BUTTON CLICKED');
  }
})

One line

document.querySelectorAll("whatever").forEach(elem => elem.addEventListener("input", fn))

I always recommend delegation - if the inputs are in the same container, then you can do this

window.addEventListener("DOMContentLoaded", function() { // on page load
  document.getElementById("inputContainer").addEventListener("input", function(e) { // passing the event
    const tgt = e.target;
    const id = tgt.id;
    console.log("You typed in",id)
  });
});

<div id="inputContainer">
  <h1>Start typing or paste</h1>
  <input id="element1">
  <input id="element2">
</div>

I cannot claim credit for this solution but I found a great solution here.

https://www.kirupa.com/html5/handling_events_for_many_elements.htm

    var theParent = document.querySelector("#theDude");
    theParent.addEventListener("click", doSomething, false);

    function doSomething(e) {
        if (e.target !== e.currentTarget) {
            var clickedItem = e.target.id;
            alert("Hello " + clickedItem);
        }
        e.stopPropagation();
    }

Maybe it will help you

let all_btn = document.querySelectorAll("button");
all_btn.forEach(function(btn) {
    btn.addEventListener("click", function() {
        console.log(this.innerHTML + " is clicked")
    });
});

// one line code
// let all_btn=document.querySelectorAll("button");all_btn.forEach(function(n){n.addEventListener("click",function(){console.log(this.innerHTML+" is clicked")})});

<button>button 1</button>
<button>button 2</button>
<button>button 3</button>

If you are using Javascript through Electron and you have a list of buttons, you can use this code to add an EventListener to each button. I'm actually using this method because classical Javascript methods (map(), forEach() ...) weren't supported anymore.

let buttons = document.getElementsByClassName('className');
for(let i = 0; i<buttons.length; i++){
   buttons[i].addEventListener('click', () => {
      /*put your code here*/
   });
}

The easiest way so far I've learned.

// Get an array of buttons from the page
var buttons = document.querySelectorAll(".btns");

// Loop through the resulting array
for(var i = 0; i < buttons.length; i++){
  buttons[i].addEventListener("click", function() {
    console.log("Hello World");
  });
}

Example:

const element1 = document.querySelector("#element1");
const element2 = document.querySelector("#element2");

[element1, element2].map(element => element.addEventListener("click", function() {
  /*some expressions :)*/
}))

You can add an event listener to multiple elements using the path key of the click event object.

document.addEventListener('click', function(e){
  //e.path[0].id;
  //e.path[0].tagName;
  //e.path[0].className;
  if(e.path[0].className==="my-element"){
    console.log("clicked");
  }
})

Example for initializing one unique event listener specific to each element.

You can use the slider to show the values in realtime, or check the console.

On the <input> element I have a attr tag called data-whatever. You can use that to customize each event listener further.

sliders = document.querySelectorAll("input");
sliders.forEach(item=> {
  item.addEventListener('input', (e) => {
    console.log(`${item.getAttribute("data-whatever")} is this value: ${e.target.value}`);
    item.nextElementSibling.textContent = e.target.value;
  });
})

.wrapper {
  display: flex;
}
span {
  padding-right: 30px;
  margin-left: 5px;
}
* {
  font-size: 12px
}

<div class="wrapper">
  <input type="range" min="1" data-whatever="size" max="800" value="50" id="sliderSize">
  <em>50</em>
  <span>Size</span>
  <br>
  <input type="range" min="1" data-whatever="OriginY" max="800" value="50" id="sliderOriginY">
  <em>50</em>
  <span>OriginY</span>
  <br>
  <input type="range" min="1" data-whatever="OriginX" max="800" value="50" id="sliderOriginX">
  <em>50</em>
  <span>OriginX</span>
</div>

If you have a DOM Collection, I suggest you to use the for ... of

In this MDN web doc you can see the details, but, for example, if you have:

HTMLCollection(6) [a.example, a.example, a.example, a.example, a.example, a.example]

You can:

let arrayElements = document.getElementsByClassName('example');
for (let element of arrayElements) {
    element.addEventListener("click", function() {
        console.log('Whoa! You clicked me')
    });

And ta-dah! ;)

Here's what I used to set a click evenhandler on every span in my HTML (each span contains an emoji). When you click it, it will alert the emoji in the sample code.

Array.from(document.querySelectorAll("span")).map(element => element.addEventListener("click", function() {
  alert(element.innerHTML);
}));

div{background: whitesmoke;}
span{ont-size:x-large;
    cursor:pointer;}

<div>
  <span>&#128512;</span>
  <span>&#128513;</span>
  <span>&#128514;</span>
  <span>&#128515;</span>
  <span>&#128516;</span>
  <span>&#128517;</span>
  <span>&#128518;</span>
  <span>&#128519;</span>
  <span>&#128520;</span>
  <span>&#128521;</span>
  <span>&#128522;</span>
  <span>&#128523;</span>
</div>

First include jQuery then after you have included, add this script below.

Html code:

<script>
    $('.greadingButton').on('click', function () {
        $('.greadingButton').removeClass('selected');
        $(this).addClass('selected');
    });
</script>

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