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ParentNode.prepend

This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The ParentNode.prepend method inserts a set of Node objects or DOMString objects before the first child of the ParentNode. DOMString objects are inserted as equivalent Text nodes.

Syntax

[Throws, Unscopable] 
void ParentNode.prepend((Node or DOMString)... nodes);

Parameters

nodes
A set of Node or DOMString objects to insert.

Exceptions

Examples

Prepending an element

var parent = document.createElement("div");
var p = document.createElement("p");
var span = document.createElement("span");
parent.append(p);
parent.prepend(span);

console.log(parent.childNodes); // NodeList [ <span>, <p> ]

Prepending text

var parent = document.createElement("div");
parent.append("Some text");
parent.prepend("Headline: ");

console.log(parent.textContent); // "Headline: Some text"

Appending an element and text

var parent = document.createElement("div");
var p = document.createElement("p");
parent.prepend("Some text", p);

console.log(parent.childNodes); // NodeList [ #text "Some text", <p> ]

ParentNode.prepend() is unscopable

The prepend() method is not scoped into the with statement. See Symbol.unscopables for more information.

var parent = document.createElement("div");

with(parent) { 
  prepend("foo");
}
// ReferenceError: prepend is not defined 

Polyfill

You can polyfill the prepend() method in Internet Explorer 9 and higher with the following code:

// from: https://github.com/jserz/js_piece/blob/master/DOM/ParentNode/prepend()/prepend().md
(function (arr) {
  arr.forEach(function (item) {
    if (item.hasOwnProperty('prepend')) {
      return;
    }
    Object.defineProperty(item, 'prepend', {
      configurable: true,
      enumerable: true,
      writable: true,
      value: function prepend() {
        var argArr = Array.prototype.slice.call(arguments),
          docFrag = document.createDocumentFragment();
        
        argArr.forEach(function (argItem) {
          var isNode = argItem instanceof Node;
          docFrag.appendChild(isNode ? argItem : document.createTextNode(String(argItem)));
        });
        
        this.insertBefore(docFrag, this.firstChild);
      }
    });
  });
})([Element.prototype, Document.prototype, DocumentFragment.prototype]);

Specification

Specification Status Comment
DOM
The definition of 'ParentNode.prepend()' in that specification.
Living Standard Initial definition.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 54.0 49 (49) ? 39 ?
Feature Android Android Webview Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile Chrome for Android
Basic support No support 54.0 49.0 (49) ? 39 ? 54.0

See also

© 2005–2017 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/ParentNode/prepend