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>
