Document: prepend() 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 Document.prepend() method
inserts a set of Node objects or strings before
the first child of the document. Strings
are inserted as equivalent Text nodes.
This method prepends a child to a Document. To prepend to an arbitrary element in the tree, see Element.prepend().
Syntax
prepend(param1)
prepend(param1, param2)
prepend(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
>Prepending a root element to a document
If you try to prepend an element to an existing HTML document,
it might throw a HierarchyRequestError DOMException given a <html> element already exists.
let html = document.createElement("html");
document.prepend(html);
// HierarchyRequestError: The operation would yield an incorrect node tree.
If you are creating a new document without any existing element, you can prepend a root HTML element (or a root SVG element):
let doc = new Document();
let html = document.createElement("html");
doc.prepend(html);
doc.children; // HTMLCollection [<html>]
Specifications
| Specification |
|---|
| DOM> # ref-for-dom-parentnode-prepend①> |