📄 playwright-python/java/docs/api/class-selectors

File: class-selectors.md | Updated: 11/18/2025

Source: https://playwright.dev/java/docs/api/class-selectors

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Selectors can be used to install custom selector engines. See extensibility for more information.

Methods​

register​

Added before v1.9 selectors.register

Selectors must be registered before creating the page.

Usage

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

// Script that evaluates to a selector engine instance. The script is evaluated in the page context.String createTagNameEngine = "{\n" +  "  // Returns the first element matching given selector in the root's subtree.\n" +  "  query(root, selector) {\n" +  "    return root.querySelector(selector);\n" +  "  },\n" +  "  // Returns all elements matching given selector in the root's subtree.\n" +  "  queryAll(root, selector) {\n" +  "    return Array.from(root.querySelectorAll(selector));\n" +  "  }\n" +  "}";// Register the engine. Selectors will be prefixed with "tag=".playwright.selectors().register("tag", createTagNameEngine);Browser browser = playwright.firefox().launch();Page page = browser.newPage();page.setContent("<div><button>Click me</button></div>");// Use the selector prefixed with its name.Locator button = page.locator("tag=button");// Combine it with built-in locators.page.locator("tag=div").getByText("Click me").click();// Can use it in any methods supporting selectors.int buttonCount = (int) page.locator("tag=button").count();browser.close();

Arguments

  • name String #

    Name that is used in selectors as a prefix, e.g. {name: 'foo'} enables foo=myselectorbody selectors. May only contain [a-zA-Z0-9_] characters.

  • script String | Path #

    Script that evaluates to a selector engine instance. The script is evaluated in the page context.

  • options Selectors.RegisterOptions (optional)

    • setContentScript boolean (optional)#

      Whether to run this selector engine in isolated JavaScript environment. This environment has access to the same DOM, but not any JavaScript objects from the frame's scripts. Defaults to false. Note that running as a content script is not guaranteed when this engine is used together with other registered engines.

Returns

setTestIdAttribute​

Added in: v1.27 selectors.setTestIdAttribute

Defines custom attribute name to be used in Page.getByTestId() . data-testid is used by default.

Usage

Selectors.setTestIdAttribute(attributeName);

Arguments