ParentNode.replaceChildren()

The ParentNode.replaceChildren() method replaces the existing children of a Node with a specified new set of children. These can be DOMString or Node objects.

Syntax

// [Throws, Unscopable]
ParentNode.replaceChildren(...nodesOrDOMStrings) // returns undefined

Parameters

nodesOrDOMStrings

A set of Node or DOMString objects to replace the ParentNode's existing children with. If no replacement objects are specified, then the ParentNode is emptied of all child nodes.

Exceptions

• HierarchyRequestError: The constraints of the node tree are violated.

Examples

Emptying a node

replaceChildren() provides a very convenient mechanism for emptying a node of all its children. You simply call it on the parent node without any argument specified:

myNode.replaceChildren();

Transferring nodes between parents

replaceChildren() enables you to easily transfer nodes between parents, without having to resort to verbose looping code. For example, say we have a simple application allowing you to choose what food you want for your party. This HTML might look something like this:

<h2>Party food option list</h2>

<main>
  <div>
    <label for="no">No thanks!</label>

    <select id="no" multiple size="10">
      <option>Apples</option>
      <option>Oranges</option>
      <option>Grapes</option>
      <option>Bananas</option>
      <option>Kiwi fruits</option>
      <option>Chocolate cookies</option>
      <option>Peanut cookies</option>
      <option>Chocolate bars</option>
      <option>Ham Sandwiches</option>
      <option>Cheese Sandwiches</option>
      <option>Falafel sandwiches</option>
      <option>Ice cream</option>
      <option>Jelly</option>
      <option>Carrot sticks and houmous</option>
      <option>Margherita pizza</option>
      <option>Pepperoni pizza</option>
      <option>Vegan veggie pizza</option>
    </select>
  </div>

  <div class="buttons">
    <button id="to-yes">Transfer to "Yes" --&gt;</button>
    <button id="to-no">&lt;-- Transfer to "No"</button>
  </div>

  <div>
    <label for="yes">Yes please!</label>

    <select id="yes" multiple size="10">

    </select>
  </div>
</main>

It would make sense to use some simple CSS to lay out the two select lists in a line alongside one another, with the control buttons in between them:

main {
  display: flex;
}

div {
  margin-right: 20px;
}

label, button {
  display: block;
}

.buttons {
  display: flex;
  flex-flow: column;
  justify-content: center;
}

select {
  width: 200px;
}

What we want to do is transfer any selected options in the "no" list over to the "yes" list when the "yes" button is pressed, and transfer any selected options in the "yes" list over to the "no" list when the "no" button is pressed.

To do this, we give each of the buttons a click event handler, which collects together the selected options you want to transfer in one constant, and the existing options in the list you are transferring to in another constant. It then calls replaceChildren() on the list to transfer the options to, using the spread operator to pass in all the options contained in both constants.

const noSelect = document.getElementById('no');
const yesSelect = document.getElementById('yes');
const noBtn = document.getElementById('to-no');
const yesBtn = document.getElementById('to-yes');

yesBtn.addEventListener('click', () => {
  const selectedTransferOptions = document.querySelectorAll('#no option:checked');
  const existingYesOptions = document.querySelectorAll('#yes option');
  yesSelect.replaceChildren(...selectedTransferOptions, ...existingYesOptions);
});

noBtn.addEventListener('click', () => {
  const selectedTransferOptions = document.querySelectorAll('#yes option:checked');
  const existingNoOptions = document.querySelectorAll('#no option');
  noSelect.replaceChildren(...selectedTransferOptions, ...existingNoOptions);
});

The end result looks like this:

Specification

Browser compatibility

See also

• ParentNode and ChildNode
• ParentNode.prepend()
• ParentNode.append()
• NodeList