DocumentFragment
Baseline Widely available *
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
* Some parts of this feature may have varying levels of support.
TheDocumentFragment interface represents a minimal document object that has no parent.
It is used as a lightweight version ofDocument that stores a segment of a document structure comprised of nodes just like a standard document. The key difference is due to the fact that the document fragment isn't part of the active document tree structure. Changes made to the fragment don't affect the document.
In this article
Constructor
DocumentFragment()Creates and returns a new
DocumentFragmentobject.
Instance properties
This interface has no specific properties, but inherits those of its parent,Node.
DocumentFragment.childElementCountRead onlyReturns the amount of child
elementstheDocumentFragmenthas.DocumentFragment.childrenRead onlyReturns a live
HTMLCollectioncontaining all objects of typeElementthat are children of theDocumentFragmentobject.DocumentFragment.firstElementChildRead onlyReturns the
Elementthat is the first child of theDocumentFragmentobject, ornullif there is none.DocumentFragment.lastElementChildRead onlyReturns the
Elementthat is the last child of theDocumentFragmentobject, ornullif there is none.
Instance methods
This interface inherits the methods of its parent,Node.
DocumentFragment.append()Inserts a set of
Nodeobjects or strings after the last child of the document fragment.DocumentFragment.prepend()Inserts a set of
Nodeobjects or strings before the first child of the document fragment.DocumentFragment.querySelector()Returns the first
Elementnode within theDocumentFragment, in document order, that matches the specified selectors.DocumentFragment.querySelectorAll()Returns a
NodeListof all theElementnodes within theDocumentFragmentthat match the specified selectors.DocumentFragment.moveBefore()Moves a given
Nodeinside the invokingDocumentFragmentas a direct child, before a given reference node, without removing and then inserting the node.DocumentFragment.replaceChildren()Replaces the existing children of a
DocumentFragmentwith a specified new set of children.DocumentFragment.getElementById()Returns the first
Elementnode within theDocumentFragment, in document order, that matches the specified ID. Functionally equivalent toDocument.getElementById().
Usage notes
A common use forDocumentFragment is to create one, assemble a DOM subtree within it, then append or insert the fragment into the DOM usingNode interface methods such asappendChild(),append(), orinsertBefore(). Doing this moves the fragment's nodes into the DOM, leaving behind an emptyDocumentFragment.
This interface is also of great use with Web components:<template> elements contain aDocumentFragment in theirHTMLTemplateElement.content property.
An emptyDocumentFragment can be created using thedocument.createDocumentFragment() method or the constructor.
Performance
The performance benefit ofDocumentFragment is often overstated. In fact, in some engines, using aDocumentFragment is slower than appending to the document in a loop as demonstrated inthis benchmark. However, the difference between these examples is so marginal that it's better to optimize for readability than performance.
Example
>HTML
<ul></ul>JavaScript
const ul = document.querySelector("ul");const fruits = ["Apple", "Orange", "Banana", "Melon"];const fragment = new DocumentFragment();for (const fruit of fruits) { const li = document.createElement("li"); li.textContent = fruit; fragment.append(li);}ul.append(fragment);Result
Specifications
| Specification |
|---|
| DOM> # interface-documentfragment> |