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Element: before() method - Web APIs | MDN
Element: before() method
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since April 2018.
The Element.before() method inserts a set of
Node objects or strings in the children list of this
Element's parent, just before this Element.
Strings are inserted as equivalent Text nodes.
Syntax
js
before(param1)
before(param1, param2)
before(param1, param2, /* …, */ paramN)
Parameters
param1, …,paramN-
A set of
Nodeobjects or strings to insert.
Return value
None (undefined).
Exceptions
HierarchyRequestErrorDOMException-
Thrown when the node cannot be inserted at the specified point in the hierarchy.
Examples
Inserting an element
js
let container = document.createElement("div");
let p = document.createElement("p");
container.appendChild(p);
let span = document.createElement("span");
p.before(span);
console.log(container.outerHTML);
// "<div><span></span><p></p></div>"
Inserting text
js
let container = document.createElement("div");
let p = document.createElement("p");
container.appendChild(p);
p.before("Text");
console.log(container.outerHTML);
// "<div>Text<p></p></div>"
Inserting an element and text
js
let container = document.createElement("div");
let p = document.createElement("p");
container.appendChild(p);
let span = document.createElement("span");
p.before(span, "Text");
console.log(container.outerHTML);
// "<div><span></span>Text<p></p></div>"
Specifications
| Specification |
|---|
| DOM # ref-for-dom-childnode-before① |
Browser compatibility
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