playwright/docs/selectors.md

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Selector engines

Playwright supports multiple selector engines used to query elements in the web page.

Selector can be used to obtain ElementHandle (see page.$() for example) or shortcut element operations to avoid intermediate handle (see page.click() for example).

Selector syntax

Selector is a string that consists of one or more clauses separated by >> token, e.g. clause1 >> clause2 >> clause3. When multiple clauses are present, next one is queried relative to the previous one's result.

Each clause contains a selector engine name and selector body, e.g. engine=body. Here engine is one of the supported engines (e.g. css or a custom one). Selector body follows the format of the particular engine, e.g. for css engine it should be a css selector. Body format is assumed to ignore leading and trailing whitespaces, so that extra whitespace can be added for readability. If selector engine needs to include >> in the body, it should be escaped inside a string to not be confused with clause separator, e.g. text="some >> text".

For example,

css=article >> css=.bar > .baz >> css=span[attr=value]

is equivalent to

document
  .querySelector('article')
  .querySelector('.bar > .baz')
  .querySelector('span[attr=value]')

For convenience, selectors in the wrong format are heuristically converted to the right format:

  • selector starting with // is assumed to be xpath=selector;
  • selector starting with " is assumed to be text=selector;
  • otherwise selector is assumed to be css=selector.

Examples

// queries 'div' css selector
const handle = await page.$('css=div');

// queries '//html/body/div' xpath selector
const handle = await page.$('xpath=//html/body/div');

// queries '"foo"' text selector
const handle = await page.$('text="foo"');

// queries 'span' css selector inside the result of '//html/body/div' xpath selector
const handle = await page.$('xpath=//html/body/div >> css=span');

// converted to 'css=div'
const handle = await page.$('div');

// converted to 'xpath=//html/body/div'
const handle = await page.$('//html/body/div');

// converted to 'text="foo"'
const handle = await page.$('"foo"');

// queries 'span' css selector inside the div handle
const handle = await divHandle.$('css=span');

Built-in selector engines

css

CSS engine is equivalent to Document.querySelector. Example: css=.article > span:nth-child(2) li.

Note

Malformed selector not starting with // nor with # is automatically transformed to css selector. For example, Playwright converts page.$('span > button') to page.$('css=span > button'). Selectors starting with # are converted to text. Selectors starting with // are converted to xpath.

xpath

XPath engine is equivalent to Document.evaluate. Example: xpath=//html/body.

Note

Malformed selector starting with // is automatically transformed to xpath selector. For example, Playwright converts page.$('//html/body') to page.$('xpath=//html/body').

text

Text engine finds an element that contains a text node with passed text. Example: text=Login.

  • By default, the match is case-insensitive, and ignores leading/trailing whitespace. This means text= Login matches <button>loGIN </button>.
  • Text body can be escaped with double quotes for precise matching, insisting on specific whitespace and case. This means text="Login " will only match <button>Login </button> with exactly one space after "Login".
  • Text body can also be a JavaScript-like regex wrapped in / symbols. This means text=/^\\s*Login$/i will match <button> loGIN</button> with any number of spaces before "Login" and no spaces after.

Note

Malformed selector starting with " is automatically transformed to text selector. For example, Playwright converts page.click('"Login"') to page.click('text="Login"').

id, data-testid, data-test-id, data-test

Id engines are selecting based on the corresponding atrribute value. For example: data-test-id=foo is equivalent to querySelector('*[data-test-id=foo]').

Custom selector engines

Playwright supports custom selector engines, registered with selectors.register(engineFunction[, ...args]).

Selector engine should have the following properties:

  • name Selector name used in selector strings.
  • create Function to create a relative selector from root (root is either a Document, ShadowRoot or Element) to a target element.
  • query Function to query first element matching selector relative to the root.
  • queryAll Function to query all elements matching selector relative to the root.

An example of registering selector engine that queries elements based on a tag name:

// Must be a function that evaluates to a selector engine instance.
const createTagNameEngine = () => ({
  // Selectors will be prefixed with "tag=".
  name: 'tag',

  // Creates a selector that matches given target when queried at the root.
  // Can return undefined if unable to create one.
  create(root, target) {
    return root.querySelector(target.tagName) === target ? target.tagName : undefined;
  },

  // Returns the first element matching given selector in the root's subtree.
  query(root, selector) {
    return root.querySelector(selector);
  },

  // Returns all elements matching given selector in the root's subtree.
  queryAll(root, selector) {
    return Array.from(root.querySelectorAll(selector));
  }
});

// Register the engine.
await selectors.register(createTagNameEngine);

// Now we can use 'tag=' selectors.
const button = await page.$('tag=button');

// We can combine it with other selector engines.
await page.click('tag=div >> text="Click me"');

// We can use it in any methods supporting selectors.
const buttonCount = await page.$$eval('tag=button', buttons => buttons.length);