Used to change the appearance of the content of a post when the_content() or the_content_rss() is called from a theme. This filter is also applied to the content of a post when an excerpt or trackback is created from the content.
the_content($content)
Will boldface the word "blog" wherever it appears in the post content without changing the content in the database:
add_filter('the_content', array('foo_bar', 'the_content_filter'));
class foo_bar {
function the_content_filter($content) {
return str_replace('blog', '<strong>blog</strong>', $content);
}
}