ContextQMD
Back to Content

tabs.detectLanguage()

files/en-us/mozilla/add-ons/webextensions/api/tabs/detectlanguage/index.md

latest4.3 KB
Original Source

Detects the primary language of the content in a tab, using the Compact Language Detector (CLD).

This is an asynchronous function that returns a Promise.

Syntax

js-nolint
let detecting = browser.tabs.detectLanguage(
  tabId,                  // optional integer
  callback                // optional function
)

Parameters

  • tabId {{optional_inline}}
    • : integer. Defaults to the active tab of the current window.
  • callback {{optional_inline}}
    • : function. Currently, if a tabId is specified, this method uses this callback to return the results instead of returning a promise. The callback receives as its only input parameter a string containing the detected language code such as en or fr.

Return value

A Promise that will be fulfilled with a string representing an ISO language code such as en or fr. For a complete list of languages supported by this method, see kLanguageInfoTable. For an unknown language, "und" will be returned (but see bug 1288263). If any error occurs the promise will be rejected with an error message.

Examples

Detect and log the language of the active tab when the user clicks a browser action:

js
function onLanguageDetected(lang) {
  console.log(`Language is: ${lang}`);
}

function onError(error) {
  console.log(`Error: ${error}`);
}

browser.browserAction.onClicked.addListener(() => {
  browser.tabs.detectLanguage().then(onLanguageDetected, onError);
});

Detect and log the language of every open tab when the user clicks a browser action (note that this example requires the "tabs" permission):

js
function onLanguageDetected(url, lang) {
  console.log(`Language in ${url} is: ${lang}`);
}

function onError(error) {
  console.log(`Error: ${error}`);
}

function detectLanguages(tabs) {
  for (const tab of tabs) {
    browser.tabs
      .detectLanguage(tab.id)
      .then((lang) => onLanguageDetected(tab.url, lang), onError);
  }
}

browser.browserAction.onClicked.addListener(() => {
  browser.tabs.query({}).then(detectLanguages, onError);
});

{{WebExtExamples}}

Browser compatibility

{{Compat}}

[!NOTE] This API is based on Chromium's chrome.tabs API. This documentation is derived from tabs.json in the Chromium code.

<!-- // Copyright 2015 The Chromium Authors. All rights reserved. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following disclaimer // in the documentation and/or other materials provided with the // distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived from // this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -->