YII Framework框架教程之国际化实现方法

/**
* Translates a message to the specified language.
* Starting from version 1.0.2, this method supports choice format (see {@link CChoiceFormat}),
* i.e., the message returned will be chosen from a few candidates according to the given
* number value. This feature is mainly used to solve plural format issue in case
* a message has different plural forms in some languages.
* @param string $category message category. Please use only word letters. Note, category 'yii' is
* reserved for Yii framework core code use. See {@link CPhpMessageSource} for
* more interpretation about message category.
* @param string $message the original message
* @param array $params parameters to be applied to the message using <code>strtr</code>.
* Starting from version 1.0.2, the first parameter can be a number without key.
* And in this case, the method will call {@link CChoiceFormat::format} to choose
* an appropriate message translation.
* Starting from version 1.1.6 you can pass parameter for {@link CChoiceFormat::format}
* or plural forms format without wrapping it with array.
* @param string $source which message source application component to use.
* Defaults to null, meaning using 'coreMessages' for messages belonging to
* the 'yii' category and using 'messages' for the rest messages.
* @param string $language the target language. If null (default), the {@link CApplication::getLanguage application language} will be used.
* This parameter has been available since version 1.0.3.
* @return string the translated message
* @see CMessageSource
*/
public static function t($category,$message,$params=array(),$source=null,$language=null)
{

Yii::t('app', 'Path alias "{alias}" is redefined.',
  array('{alias}'=>$alias))