> For the complete documentation index, see [llms.txt](https://documentation.ajaxsearchpro.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://documentation.ajaxsearchpro.com/plugin-api/filters-list-and-usage.md).

# Filters list and usage

Filters are used to modify data on specific events. You can create functions based on the filters list below with the available parameters. Filters are a great way of modifying results without touching the code.

## Usage examples

Here you can see two basic examples of filter usage. One is adding [category titles to the result titles](https://wp-dreams.com/knowledge-base/showing-the-category-titles-in-the-result-title/), and second is a simple [result numbering](https://wp-dreams.com/knowledge-base/numbering-the-results/).

For more examples, check the [knowledge base](https://wp-dreams.com/knowledgebase/).

```
/** 
 * Add category titles to result titles
 * 
 * @link: https://wp-dreams.com/knowledge-base/showing-the-category-titles-in-the-result-title/
 */
add_filter( 'asp_pagepost_results', 'asp_add_category_titles', 1, 1 );

function asp_add_category_titles( $pageposts ) {
  foreach ($pageposts as $k=>$v) {

    // Get the post categories
    $post_categories = wp_get_post_categories( $pageposts[$k]->id );
    $cats = "";

    // Concatenate category names to the $cats variable
    foreach($post_categories as $c){
        $cat = get_category( $c );
        $cats = " ".$cat->name;
    }                 

    // Modify the post title
    $pageposts[$k]->title  .= " ".$cats;
  }

  return $pageposts;
}


/** 
 * Numbering the results
 * 
 * @link: https://wp-dreams.com/knowledge-base/numbering-the-results/
 */
add_filter( 'asp_results', 'asp_number_results', 1, 1 );

function asp_number_results( $results ) {
  var $num = 1;
  foreach ($results as $k=>$v) {
    // Modify the post title
    $results[$k]->title  = $num . ". " . $results[$k]->title;
    $num++;
  }

  return $results;
}
```

## Filters list

```
/** 
 * Filters, if caching is not activated 
 *
 * Parameters explained:
 *      $r -> the result object (id, title, content, link, author, date)
 *      $results -> associative array of result objects
 *      $s -> search phrase
 */

$allpageposts = apply_filters( 'asp_pagepost_results', $allpageposts );
$allcommentsresults = apply_filters( 'asp_comment_results', $allcommentsresults );
$buddypresults = apply_filters( 'asp_buddyp_results', $buddypresults );
$blogresults = apply_filters( 'asp_blog_results', $blogresults ); 
$results = apply_filters( 'asp_only_keyword_results', $results );
$results = apply_filters( 'asp_only_non_keyword_results', $results );
$results = apply_filters( 'asp_results', $results );
$s = apply_filters( 'asp_search_phrase_before_cleaning', $s );
$s = apply_filters( 'asp_search_phrase_after_cleaning', $s );

$r = apply_filters('asp_result_before_prostproc', $r); 
$r->title = apply_filters( 'asp_result_title_before_prostproc' , $r->title, $r->id);
$r->content = apply_filters( 'asp_result_content_before_prostproc' , $r->content, $r->id);
$r->image = apply_filters( 'asp_result_image_before_prostproc' , $r->image, $r->id);
$r->author = apply_filters( 'asp_result_author_before_prostproc' , $r->author, $r->id);
$r->date = apply_filters( 'asp_result_date_before_prostproc' , $r->date, $r->id);

$r = apply_filters('asp_result_after_prostproc', $r); 
$r->title = apply_filters( 'asp_result_title_after_prostproc' , $r->title, $r->id);
$r->content = apply_filters( 'asp_result_content_after_prostproc' , $r->content, $r->id);
$r->image = apply_filters( 'asp_result_image_after_prostproc' , $r->image, $r->id);
$r->author = apply_filters( 'asp_result_author_after_prostproc' , $r->author, $r->id);
$r->date = apply_filters( 'asp_result_date_after_prostproc' , $r->date, $r->id);

/* With cache activated */
// The HTML output of cached content 
$cache_content = apply_filters( 'asp_cached_content', $cache_content);
```


---

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