Adding a class to <body> in a module in Drupal 7
In Drupal 6, I would often resort to using my theme's template.php file to implement template_preprocess(), and add in the class to Drupal's $body_classes array. In Drupal 7, some new hooks were introduced that allow me to do this more easily, and inside my .module files.
Introducing hook_preprocess_HOOK()
<?php/** * Implements hook_preprocess_HOOK(). */function custom_preprocess_html(&$vars) { $vars['classes_array'][] = 'my-class-here';}?>