How to check the particular Gutenberg block exists in post_content

Paula

I am looking for a way to implement a particular design based on the Gutenberg block but I don't how to achieve this. For example, I want to add a class based on the heading block.

I only know to the way to get the post content with post id with get_the_content( get_the_ID() ), could anyone help me to find out the particular block.

Jacob

Gutenberg blocks are stored with the database in the following format. Take a look for the paragraph tag.

<!-- wp:paragraph -->
<p>Here is the paragraph content.</p>
<!-- /wp:paragraph -->

And you can use the regular expression to find out the particular block.

// Get the post_content
$post_content = get_the_content( get_the_ID() );

// Get all matches in between <!-- /wp: --> strings
preg_match_all('<!-- /wp:(.*?) -->', $post_content, $blocks); 

// Post content contains a wp:heading block
if ( in_array( 'heading', $blocks[1] ) ) {
    // Your codes
}
else {
    // Your codes
}

James

Hi Paula, Jacob is correct, you can get the desired block by using the regular expression. Or If you are using the WordPress 5.0+ version, then you can use the parse_blocks() function get the particular Gutenberg block.

Take a look to sample codes to get it more clear.

$post_content = get_the_content( get_the_ID() );

// Check if blocks exists
if ( has_blocks( $post_content ) ) {
	$blocks = parse_blocks( $post_content );

	// Check for the Heading block
	if ( $blocks[0]['blockName'] === 'core/heading' ) {
		// Your codes here
	}
}