Applying shortcode actions

@sterndata,

Thanks again. I tried adding the filter, and seems to work okay. HOWEVER, in the plugin code, I was working with a creating, setting, and checking the value for a $_SESSION variable. How would this work now since now I’ve managed to eliminate the need for the shortcode? Below is a breakdown of the changes I made:

In the main PHP code for the plugin, I added add_filter( 'the_content', 'hash_links' ); in one of the functions that get called upon instantiation.

I then added the following functions OUTSIDE the plugin class:

// Replace all PDF links with the hash values.
function hash_links( $content ) {
  $regex = "/(http|https|ftp|ftps)\:\/\/[a-zA-Z0-9\-\.]+\.[a-zA-Z]{2,3}(\/\S*\.pdf)+/";
  
  preg_match_all($regex, $content, $link_matches);
  
  $content .= "<BR><BR><BR>";
  
  foreach($link_matches[0] as $match){
    $content = str_replace($match, hashLink($match), $content);
  }
  
  return $content;
}

// This will return the hash value for the link. Here, we will also add the hash value and plaintext to the option table.
function hashLink($link) {
  $ins = $GLOBALS['reCaptchaProtectedDownloadsCore'];
  $hash = apply_filters("rcpdl_hash", md5($link), $link);
  
  if ( $ins->isNetworkActive() ){
    add_site_option("rcpdl_{$hash}", esc_attr(esc_url( $link )));
  } else{
    add_option("rcpdl_{$hash}", esc_attr(esc_url( $link )));
  }
  
  return apply_filters('rcpdl_link', "#rcpdl={$hash}", $link, $hash);
}

Ah, got it. What I had was actually SESSION info AND a javascript variable that controlled the link behavior. The javascript variable kept being reset because the link would open in the same window/tab, thereby refreshing the page on return, and the javascript with it.

In short, I just had to change it so that the links open in new tabs/windows instead. Thanks again for your help in resolving my first issue.