How to prepend text to the_content, but after img/shortcode

I was trying to add some text to the beginning of every post (the text comes from post_meta, but for this example let’s assume it’s static text).

Here’s what I tried:

add_filter('the_content', function($content)
{
    return 'Text from meta - ' . $content;
});

However, if the post starts with a – usually floated – image (sometimes even wrapped in a caption shortcode), the added text will come before the image.

I would like for the text to be prepended to the first paragraph in the post. Is there any way to accomplish this without parsing the full HTML?

Answers:

Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found the post helpful (or not), leave a comment & I’ll get back to you as soon as possible.

Method 1

I finally settled on using a regex, with a limit of 1 so it only happens on the first paragraph:

add_filter('the_content', function($content)
{
    $content = preg_replace('/<p[^>]*>/', '$1Text from meta - ', $content, 1);
    return $content;
});

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0