I want to add a body class for the content type of each node. Drupal already provides this, but it isn't always consistent between the Node view, the Node/Add view and the Node/Edit view. This makes theming difficult. 

Here is my code in template.php

    function MYTHEME_preprocess_html(&$variables) {
        
        // Add Content type name to classes
        $content_type = $variables['page']['content']['system_main']['type']['#value'];
        $content_type_class = 'content-type-'.drupal_html_class($content_type);
        $variables['classes_array'][] = $content_type_class;
    
    }


It works but I get this error message:

> Notice: Undefined index: type in wintheme_preprocess_html()

On Stack Exchange, [it says the best approach is to use Isset()][1].

If I do this, the error message goes away, but so does the class.

How can I keep my class working without the error message. 


  [1]: https://stackoverflow.com/questions/4261133/php-notice-undefined-variable-and-notice-undefined-index