The insertAdjacentElement() method of the Element interface inserts a given element node at a given position relative to the element it is invoked upon.
insertAdjacentElement(position, element)positionA string representing the position relative to the targetElement; must match (case-insensitively) one of the following strings:
'beforebegin': Before the targetElement itself.'afterbegin': Just inside the targetElement, before its first child.'beforeend': Just inside the targetElement, after its last child.'afterend': After the targetElement itself.elementThe element to be inserted into the tree.
The element that was inserted, or null, if the insertion failed.
SyntaxError DOMExceptionThrown if the position specified is not a recognized value.
TypeErrorThrown if the element specified is not a valid element.
<!-- beforebegin -->
<p>
<!-- afterbegin -->
foo
<!-- beforeend -->
</p>
<!-- afterend -->Note: The beforebegin and afterend positions work only if the node is in a tree and has an element parent.
In this example we have a row of square boxes. The user can select a box by clicking on it: this gives the box a different border, to show that it is selected.
If a box is selected, and the user presses the "Insert before" or "Insert after" buttons, then the code creates a new box, gives it a random color, and inserts it before or after the selected box.
<p>
Click colored box to select it, then use the first two buttons below to insert
elements before and after your selection.
</p>
<section>
<div></div>
<div></div>
<div></div>
<div></div>
</section>
<button class="before">Insert before</button>
<button class="after">Insert after</button>
<button class="reset">Reset demo</button>div {
width: 50px;
height: 50px;
margin: 3px;
border: 3px solid black;
display: inline-block;
background-color: red;
}
.selected {
border-color: aqua;
}let selectedElem;
// Function to select a new element
function selectElement(newSelection) {
if (selectedElem !== newSelection) {
if (selectedElem) {
selectedElem.classList.remove("selected");
}
selectedElem = newSelection;
newSelection.classList.add("selected");
}
}
// Add click handlers that select the clicked element
const initElems = Array.from(document.querySelectorAll("section div"));
for (const initElem of initElems) {
initElem.addEventListener("click", (e) => selectElement(e.target));
}
// Add click handlers to "beforeBtn" and "afterBtn"
// to insert a new element before/after the selected element
const beforeBtn = document.querySelector(".before");
const afterBtn = document.querySelector(".after");
beforeBtn.addEventListener("click", () => insertNewElement("beforebegin"));
afterBtn.addEventListener("click", () => insertNewElement("afterend"));
function insertNewElement(position) {
function random() {
return Math.floor(Math.random() * 255);
}
if (!selectedElem) {
return;
}
const newElement = document.createElement("div");
const randomColor = `rgb(${random(255)} ${random(255)} ${random(255)})`;
newElement.style.backgroundColor = randomColor;
newElement.addEventListener("click", (e) => selectElement(e.target));
selectedElem.insertAdjacentElement(position, newElement);
}
// Reset the example
const resetBtn = document.querySelector(".reset");
resetBtn.addEventListener("click", () => window.location.reload(true));Element.insertAdjacentHTML()Element.insertAdjacentText()Node.insertBefore() (similar to beforebegin, with different arguments)Node.appendChild() (same effect as beforeend)