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web api instance method

Document: prepend() method

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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 prepend().

Syntax

prepend(param1)
prepend(param1, param2)
prepend(param1, param2, /* …, */ paramN)

Parameters

  • param1, …, paramN
    • : A set of Node objects or strings to insert.

Return value

None (undefined).

Exceptions

  • HierarchyRequestError DOMException
    • : 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

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also