January 8, 2015
For a specific styling i needed to be able to add elements, specifically a <span> element inside the H2 tags automatically.
Outside of the content is easy
To achieve this for titles outside of the_content is pretty easily done with the $before and $after Parameters on the_title() like so, or we could just wrap the_title inside the desired tags.
<?php the_title( '<h2 class="entry-title"><span>', '</span></h2>' ); ?>
Filtering the_content
To achieve the same result for all H2 tags inside the content we need to filter the_content with a regular expression.
function pdr_add_class_to_h2( $content ){
return preg_replace( '/<h2(.*?)>(.*?)<\/h2>/', '<h2\1 class="entry-title"><span>\2</span></h2>', $content );
}
add_filter( 'the_content', 'pdr_add_class_to_h2' );
To extend this with other tags to replace, we can also pass arrays to preg_replace. Each element in $pattern will be replace by its counterpart in $replacement.
function pdr_add_class_to_titles( $content ){
$pattern = array(
'/<h2(.*?)>(.*?)<\/h2>/',
'/<h3(.*?)>(.*?)<\/h3>/',
'/<h4(.*?)>(.*?)<\/h4>/',
'/<h5(.*?)>(.*?)<\/h5>/',
'/<h6(.*?)>(.*?)<\/h6>/'
);
$replacement = array(
'<h2\1 class="entry-title"><span>\2</span></h2>',
'<h3\1 class="entry-title"><span>\2</span></h3>',
'<h4\1 class="entry-title"><span>\2</span></h4>',
'<h5\1 class="entry-title"><span>\2</span></h5>',
'<h6\1 class="entry-title"><span>\2</span></h6>',
);
return preg_replace( $pattern, $replacement, $content );
}
add_filter( 'the_content', 'pdr_add_class_to_titles' );
I found this solution in this support thread and adapted it a bit to fit my needs and replace all titles but it could basically be used to replace all kinds of stuff inside the content.