Loading extra language files
From Joomla! Documentation
Overview[edit]
Many times, you need to load extra language files in your code. An example is loading your component's language file into a module for that component. This example loads a single language file, and appends the results to the existing language strings. Following is the code that helps you do this
PHP Code[edit]
$lang =& JFactory::getLanguage();
$extension = 'com_helloworld';
$base_dir = JPATH_SITE;
$language_tag = 'en-GB';
$reload = true;
$lang->load($extension, $base_dir, $language_tag, $reload);
Following is an explanation of the variables
1. $extension - This is the extension whose language file will be loaded
2. $base_dir - Should be JPATH_SITE in case you have language files stored elsewhere. Defaults to JPATH_SITE [optional]
3. $language_tag - This is the locale string. Language files for this locale will be loaded. Defaults to the one set in backend. [optional]
4. $reload - Flag that will force a language to be reloaded if set to true. [optional]