Remove all child elements of a DOM node in JavaScript

Question

How would I go about removing all of the child elements of a DOM node in JavaScript?

Say I have the following (ugly) HTML:

    &         


        

Answer 1

If you use jQuery:

$('#foo').empty();

If you don't:

var foo = document.getElementById('foo');
while (foo.firstChild) foo.removeChild(foo.firstChild);

Answer 2

Using a range loop feels the most natural to me:

for (var child of node.childNodes) {
    child.remove();
}

According to my measurements in Chrome and Firefox, it is about 1.3x slower. In normal circumstances, this will perhaps not matter.

Answer 3

var empty_element = function (element) {

    var node = element;

    while (element.hasChildNodes()) {              // selected elem has children

        if (node.hasChildNodes()) {                // current node has children
            node = node.lastChild;                 // set current node to child
        }
        else {                                     // last child found
            console.log(node.nodeName);
            node = node.parentNode;                // set node to parent
            node.removeChild(node.lastChild);      // remove last node
        }
    }
}

This will remove all nodes within the element.

Answer 4

Option 1 A: Clearing innerHTML.

• This approach is simple, but might not be suitable for high-performance applications because it invokes the browser's HTML parser (though browsers may optimize for the case where the value is an empty string).

doFoo.onclick = () => {
  const myNode = document.getElementById("foo");
  myNode.innerHTML = '';
}

<div id='foo' style="height: 100px; width: 100px; border: 1px solid black;">
  <span>Hello</span>
</div>
<button id='doFoo'>Remove via innerHTML</button>

Option 1 B: Clearing textContent

• As above, but use .textContent. According to MDN this will be faster than innerHTML as browsers won't invoke their HTML parsers and will instead immediately replace all children of the element with a single #text node.

doFoo.onclick = () => {
  const myNode = document.getElementById("foo");
  myNode.textContent = '';
}

<div id='foo' style="height: 100px; width: 100px; border: 1px solid black;">
  <span>Hello</span>
</div>
<button id='doFoo'>Remove via textContent</button>

Option 2 A: Looping to remove every lastChild:

• An earlier edit to this answer used firstChild, but this is updated to use lastChild as in computer-science, in general, it's significantly faster to remove the last element of a collection than it is to remove the first element (depending on how the collection is implemented).
• The loop continues to check for firstChild just in case it's faster to check for firstChild than lastChild (e.g. if the element list is implemented as a directed linked-list by the UA).

doFoo.onclick = () => {
  const myNode = document.getElementById("foo");
  while (myNode.firstChild) {
    myNode.removeChild(myNode.lastChild);
  }
}

<div id='foo' style="height: 100px; width: 100px; border: 1px solid black;">
  <span>Hello</span>
</div>
<button id='doFoo'>Remove via lastChild-loop</button>

Option 2 B: Looping to remove every lastElementChild:

• This approach preserves all non-Element (namely #text nodes and <!-- comments --> ) children of the parent (but not their descendants) - and this may be desirable in your application (e.g. some templating systems that use inline HTML comments to store template instructions).
• This approach wasn't used until recent years as Internet Explorer only added support for lastElementChild in IE9.

doFoo.onclick = () => {
  const myNode = document.getElementById("foo");
  while (myNode.lastElementChild) {
    myNode.removeChild(myNode.lastElementChild);
  }
}

<div id='foo' style="height: 100px; width: 100px; border: 1px solid black;">
  <!-- This comment won't be removed -->
  <span>Hello <!-- This comment WILL be removed --></span>
  <!-- But this one won't. -->
</div>
<button id='doFoo'>Remove via lastElementChild-loop</button>

Bonus: Element.clearChildren monkey-patch:

• We can add a new method-property to the Element prototype in JavaScript to simplify invoking it to just el.clearChildren() (where el is any HTML element object).
• (Strictly speaking this is a monkey-patch, not a polyfill, as this is not a standard DOM feature or missing feature. Note that monkey-patching is rightfully discouraged in many situations.)

if( typeof Element.prototype.clearChildren === 'undefined' ) {
    Object.defineProperty(Element.prototype, 'clearChildren', {
      configurable: true,
      enumerable: false,
      value: function() {
        while(this.firstChild) this.removeChild(this.lastChild);
      }
    });
}

<div id='foo' style="height: 100px; width: 100px; border: 1px solid black;">
  <span>Hello <!-- This comment WILL be removed --></span>
</div>
<button onclick="this.previousElementSibling.clearChildren()">Remove via monkey-patch</button>

Answer 5

Here's another approach:

function removeAllChildren(theParent){

    // Create the Range object
    var rangeObj = new Range();

    // Select all of theParent's children
    rangeObj.selectNodeContents(theParent);

    // Delete everything that is selected
    rangeObj.deleteContents();
}

Answer 6

Simplest way of removing the child nodes of a node via Javascript

var myNode = document.getElementById("foo");
while(myNode.hasChildNodes())
{
   myNode.removeChild(myNode.lastChild);
}