filters - Assign IDs to headings in ACF using functions.php

I'm assigning IDs to each heading on my Wordpress site. It works fine for pages where I don't use ACF with the following code snippet in functions.php

function auto_id_headings( $content ) {

  $content = preg_replace_callback( '/(\<h[1-6](.*?))\>(.*)(<\/h[1-6]>)/i', function( $matches ) {
    if ( ! stripos( $matches[0], 'id=' ) ) :
      $matches[0] = $matches[1] . $matches[2] . ' id="' . sanitize_title( $matches[3] ) . '">' . $matches[3] . $matches[4];
    endif;
    return $matches[0];
  }, $content );

    return $content;

}
add_filter( 'the_content', 'auto_id_headings' );

However, this won't pick up headings inside ACFs so I came up with the following solution, which I also added to functions.php

function auto_id_headings_acf( $value, $post_id, $field ) {

  $content = preg_replace_callback( '/(\<h[1-6](.*?))\>(.*)(<\/h[1-6]>)/i', function( $matches ) {
    if ( ! stripos( $matches[0], 'id=' ) ) :
      $matches[0] = $matches[1] . $matches[2] . ' id="' . sanitize_title( $matches[3] ) . '">' . $matches[3] . $matches[4];
    endif;
    return $matches[0];
  }, $value );

    return $value;

}
add_filter( 'acf/format_value/type=wysiwyg', 'auto_id_headings_acf', 10, 3);

It doesn't work though. :/

Any idea what I can do to make it work? Your help would be greatly appreciated!

I'm assigning IDs to each heading on my Wordpress site. It works fine for pages where I don't use ACF with the following code snippet in functions.php

function auto_id_headings( $content ) {

  $content = preg_replace_callback( '/(\<h[1-6](.*?))\>(.*)(<\/h[1-6]>)/i', function( $matches ) {
    if ( ! stripos( $matches[0], 'id=' ) ) :
      $matches[0] = $matches[1] . $matches[2] . ' id="' . sanitize_title( $matches[3] ) . '">' . $matches[3] . $matches[4];
    endif;
    return $matches[0];
  }, $content );

    return $content;

}
add_filter( 'the_content', 'auto_id_headings' );

However, this won't pick up headings inside ACFs so I came up with the following solution, which I also added to functions.php

function auto_id_headings_acf( $value, $post_id, $field ) {

  $content = preg_replace_callback( '/(\<h[1-6](.*?))\>(.*)(<\/h[1-6]>)/i', function( $matches ) {
    if ( ! stripos( $matches[0], 'id=' ) ) :
      $matches[0] = $matches[1] . $matches[2] . ' id="' . sanitize_title( $matches[3] ) . '">' . $matches[3] . $matches[4];
    endif;
    return $matches[0];
  }, $value );

    return $value;

}
add_filter( 'acf/format_value/type=wysiwyg', 'auto_id_headings_acf', 10, 3);

It doesn't work though. :/

Any idea what I can do to make it work? Your help would be greatly appreciated!

• functions
• filters
• advanced-custom-fields

Share Improve this question asked Feb 19, 2019 at 12:02 sharkmountainsharkmountain 522 bronze badges

Add a comment  | 

1 Answer 1

Sorted by: Reset to default 0

How are you printing the contents of the ACF field in your site code?

Assuming that you have self-coded theme files, instead of using the_field() to print the field content, you should echo get_field() passed through the 'the_content' filter,

eg: echo apply_filters( 'the_content', get_field( 'my_field_name' ) );

and it will apply the modifications from your first snippet.