My articles ¶

Articles are separated into more files as there is the max lenght for each file on wiki.

• Yii v1 for beginners
• Yii v1 for beginners 2
• Yii v2 snippet guide I
• Yii v2 snippet guide II
• Yii v2 snippet guide III

Switching languages and Language in URL ¶

I already wrote how translations work. Here I will show how language can be switched and saved into the URL. So let's add the language switcher into the main menu:

echo Nav::widget([
 'options' => ['class' => 'navbar-nav navbar-right'],
 'items' => [
  ['label' => 'Language', 'items' => [
    ['label' => 'German' , 'url' => \yii\helpers\Url::current(['sys_lang' => 'de']) ],
    ['label' => 'English', 'url' => \yii\helpers\Url::current(['sys_lang' => 'en']) ],
   ],
  ]

Now we need to process the new GET parameter "sys_lang" and save it to Session in order to keep the new language. Best is to create a BaseController which will be extended by all controllers. Its content looks like this:

<?php
namespace app\controllers;
use yii\web\Controller;
class _BaseController extends Controller {
  public function beforeAction($action) {
    if (isset($_GET['sys_lang'])) {
      switch ($_GET['sys_lang']) {
        case 'de':
          $_SESSION['sys_lang'] = 'de-DE';
          break;
        case 'en':
          $_SESSION['sys_lang'] = 'en-US';
          break;
      }
    }
    if (!isset($_SESSION['sys_lang'])) {
      $_SESSION['sys_lang'] = \Yii::$app->sourceLanguage;
    }
    \Yii::$app->language = $_SESSION['sys_lang'];
    return true;
  }
}

If you want to have the sys_lang in the URL, right behind the domain name, following URL rules can be created in config/web.php:

'components' => [
 // ...
 'urlManager' => [
  'enablePrettyUrl' => true,
  'showScriptName' => false,
  'rules' => [
   // https://www.yiiframework.com/doc/api/2.0/yii-web-urlmanager#$rules-detail
   // https://stackoverflow.com/questions/2574181/yii-urlmanager-language-in-url
   // https://www.yiiframework.com/wiki/294/seo-conform-multilingual-urls-language-selector-widget-i18n
   '<sys_lang:[a-z]{2}>' => 'site',
   '<sys_lang:[a-z]{2}>/<controller:\w+>' => '<controller>',
   '<sys_lang:[a-z]{2}>/<controller:\w+>/<action:\w+>' => '<controller>/<action>',
  ],
 ],
],

Now the language-switching links will produce URL like this: http://myweb.com/en/site/index . Without the rules the link would look like this: http://myweb.com/site/index?sys_lang=en . So the rule works in both directions. When URL is parsed and controllers are called, but also when a new URL is created using the URL helper.