duskosobic
1/25/2017 - 2:59 PM

Get The First Image From a Post. Let's say you wanted to use the post thumbnail feature of WordPress, but had a whole archive of posts that

Get The First Image From a Post. Let's say you wanted to use the post thumbnail feature of WordPress, but had a whole archive of posts that would take too much time to go through. For new posts, you can be specific and use the feature as intended. For old posts, you just want to use the first image it finds in the content for the thumbnail, or a default if none present.

in_loop.php
content_copyfile_download
<?php

// use this code in the loop
if ( get_the_post_thumbnail($post_id) != '' ) {

  echo '<a href="'; the_permalink(); echo '" class="thumbnail-wrapper">';
   the_post_thumbnail();
  echo '</a>';

} else {

 echo '<a href="'; the_permalink(); echo '" class="thumbnail-wrapper">';
 echo '<img src="';
 echo catch_that_image();
 echo '" alt="" />';
 echo '</a>';

}

?>
get_first_image.php
content_copyfile_download
<?php

// add this to functions.php
function catch_that_image() {
  global $post, $posts;
  $first_img = '';
  ob_start();
  ob_end_clean();
  $output = preg_match_all('https://cdn.css-tricks.com/<img.+src=[\'"]([^\'"]+)[\'"].*>/i', $post->post_content, $matches);
  $first_img = $matches[1][0];

  if(empty($first_img)) {
    $first_img = "/path/to/default.png";
  }
  return $first_img;
}

?>