Element: querySelectorAll() method

selectors

A string containing one or more selectors to match. This string must be a valid CSS selector string; if it isn't, a SyntaxError exception is thrown.

Note that the HTML specification does not require attribute values to be valid CSS identifiers. If a class or id attribute value is not a valid CSS identifier, then you must escape it before using it in a selector, either by calling CSS.escape() on the value, or using one of the techniques described in Escaping characters. See Escaping attribute values for an example.

The selectors are applied to the entire document, not just the particular element on which querySelectorAll() is called. To restrict the selector to the element on which querySelectorAll() is called, include the :scope pseudo-class at the start of the selector. See the selector scope example.

A non-live NodeList containing one Element object for each descendant node that matches at least one of the specified selectors.

SyntaxError DOMException

Thrown if the syntax of the specified selectors string is not valid.

This example uses the attribute selector to select multiple elements with a data-name data attribute that contains "funnel-chart-percent".

<section class="box" id="sect1">
  <div data-name="funnel-chart-percent1">10.900%</div>
  <div data-name="funnel-chart-percent2">3700.00%</div>
  <div data-name="funnel-chart-percent3">0.00%</div>
</section>

const refs = [
  ...document.querySelectorAll(`[data-name*="funnel-chart-percent"]`),
];

To obtain a NodeList of all of the <p> elements contained within the element "myBox":

const matches = myBox.querySelectorAll("p");

This example returns a list of all <div> elements within "myBox" with a class of either "note" or "alert":

const matches = myBox.querySelectorAll("div.note, div.alert");

Here, we get a list of the document's <p> elements whose immediate parent element is a <div> with the class "highlighted" and which are located inside a container whose ID is "test".

const container = document.querySelector("#test");
const matches = container.querySelectorAll("div.highlighted > p");

This example uses an attribute selector to return a list of the <iframe> elements in the document that contain an attribute named "data-src":

const matches = document.querySelectorAll("iframe[data-src]");

Here, an attribute selector is used to return a list of the list items contained within a list whose ID is "userlist" which have a "data-active" attribute whose value is "1":

const container = document.querySelector("#userlist");
const matches = container.querySelectorAll("li[data-active='1']");

Once the NodeList of matching elements is returned, you can examine it just like any array. If the array is empty (that is, its length property is 0), then no matches were found.

Otherwise, you can use standard array notation to access the contents of the list. You can use any common looping statement, such as:

const highlightedItems = userList.querySelectorAll(".highlighted");

highlightedItems.forEach((userItem) => {
  deleteUser(userItem);
});

The querySelectorAll() method applies its selectors to the whole document: they are not scoped to the element on which the method is called. To scope the selectors, include the :scope pseudo-class at the start of the selector string.

HTML

In this example the HTML contains:

• two buttons: #select and #select-scope
• three nested <div> elements: #outer, #subject, and #inner
• a <pre> element which the example uses for output.

<button id="select">Select</button>
<button id="select-scope">Select with :scope</button>

<div id="outer">
  #outer
  <div id="subject">
    #subject
    <div id="inner">#inner</div>
  </div>
</div>

<pre id="output"></pre>

div {
  margin: 0.5rem;
  padding: 0.5rem;
  border: 3px #20b2aa solid;
  border-radius: 5px;
  font-family: monospace;
}

pre,
button {
  margin: 0.5rem;
  padding: 0.5rem;
}

JavaScript

In the JavaScript, we first select the #subject element.

When the #select button is pressed, we call querySelectorAll() on #subject, passing "#outer #inner" as the selector string.

When the #select-scope button is pressed, we again call querySelectorAll() on #subject, but this time we pass ":scope #outer #inner" as the selector string.

const subject = document.querySelector("#subject");

const select = document.querySelector("#select");
select.addEventListener("click", () => {
  const selected = subject.querySelectorAll("#outer #inner");
  output.textContent = `Selection count: ${selected.length}`;
});

const selectScope = document.querySelector("#select-scope");
selectScope.addEventListener("click", () => {
  const selected = subject.querySelectorAll(":scope #outer #inner");
  output.textContent = `Selection count: ${selected.length}`;
});

Result

When we press "Select", the selector selects all elements with an ID of inner that also have an ancestor with an ID of outer. Note that even though #outer is outside the #subject element, it is still used in selection, so our #inner element is found.

When we press "Select with :scope", the :scope pseudo-class restricts the selector scope to #subject, so #outer is not used in selector matching, and we don't find the #inner element.

This example shows that if an HTML document contains an id which is not a valid CSS identifier, then we must escape the attribute value before using it in querySelectorAll().

HTML

In the following code, a <div> element has an id of "this?element", which is not a valid CSS identifier, because the "?" character is not allowed in CSS identifiers.

We also have three buttons, and a <pre> element for logging errors.

<div id="container">
  <div id="this?element"></div>
</div>

<button id="no-escape">No escape</button>
<button id="css-escape">CSS.escape()</button>
<button id="manual-escape">Manual escape</button>

<pre id="log"></pre>

CSS

div {
  background-color: blue;
  margin: 1rem 0;
  height: 100px;
  width: 200px;
}

JavaScript

All three buttons, when clicked, try to select the <div>, and then set its background color to a random value.

• The first button uses the "this?element" value directly.
• The second button escapes the value using CSS.escape().
• The third button explicitly escapes the "?" character using a backslash. Note that we must also escape the backslash itself, using another backslash, like: "\\?".

const container = document.querySelector("#container");
const log = document.querySelector("#log");

function random(number) {
  return Math.floor(Math.random() * number);
}

function setBackgroundColor(id) {
  log.textContent = "";

  try {
    const elements = container.querySelectorAll(`#${id}`);
    const randomColor = `rgb(${random(255)} ${random(255)} ${random(255)})`;
    elements[0].style.backgroundColor = randomColor;
  } catch (e) {
    log.textContent = e;
  }
}

document.querySelector("#no-escape").addEventListener("click", () => {
  setBackgroundColor("this?element");
});

document.querySelector("#css-escape").addEventListener("click", () => {
  setBackgroundColor(CSS.escape("this?element"));
});

document.querySelector("#manual-escape").addEventListener("click", () => {
  setBackgroundColor("this\\?element");
});

Result

Clicking the first button gives an error, while the second and third buttons work properly.

• Locating DOM elements using selectors
• Attribute selectors in the CSS Guide
• Attribute selectors in the MDN Learning Area
• Element.querySelector()
• Document.querySelector() and Document.querySelectorAll()
• DocumentFragment.querySelector() and DocumentFragment.querySelectorAll()