How to use preprocess_comment filter in WordPress

preprocess_comment filter

Filters a comment’s data before it is sanitized and inserted into the database.

To use the preprocess_comment filter, first, you have to register it using add_filter. You can write this code into functions.php of your activated theme or in a custom WordPress Plugin.

We at WePlugins always prefer to create a custom WordPress Plugin while using hooks so nothing breaks when you update your WordPress Theme in the future.

In the below live example, we have defined a function weplugins_modify_preprocess_comment_defaults which takes 1 parameter, and we registered it using add_filter. The first parameter preprocess_comment is the name of the hook. The second parameter weplugins_modify_preprocess_comment_defaults is the name of the function which needs to be called. The third parameter is the priority of calling the hook if the same hook is used multiple times, and the last parameter is the number of arguments (if any) to be passed in the registered function.

Sometimes, you have to remove a registered hook, so you can use remove_filter to remove the preprocess_comment filter.

Parameters

Below the 1 parameter is required to use this hook.

• $commentdata: (array) Comment data.

Live Example 1

In this example, we demonstrate how to remove the URL from the comment author’s data and format the comment content properly.

    add_filter( 'preprocess_comment' , 'weplugins_preprocess_comment_remove_url' );
    function weplugins_preprocess_comment_remove_url( $commentdata ) {
       // Always remove the URL from the comment author's comment
       unset( $commentdata['comment_author_url'] );
        // If the user is speaking in all caps, lowercase the comment
       if( $commentdata['comment_content'] == strtoupper( $commentdata['comment_content'] ) ) {
          $commentdata['comment_content'] = ucwords( strtolower( $commentdata['comment_content'] ) );
       }
       return $commentdata;
    }
    

Live Example 2

Below is an example of how you can use this hook to modify the comment data based on your website’s requirements.

    function weplugins_modify_preprocess_comment_defaults($commentdata) {
        // Update the $commentdata variable according to your website requirements and return this variable. You can modify the $commentdata variable conditionally too if you want.
        return $commentdata;
    }
    // Add the filter
    add_filter( "preprocess_comment", "weplugins_modify_preprocess_comment_defaults", 10, 1 );
    

Live Example 3

To remove a hook callback, use the example below. Please make sure to provide the same callback function name, priority, and number of arguments while removing the hook callback.

    remove_filter( "preprocess_comment", "weplugins_modify_preprocess_comment_defaults", 10, 1 );
    

Contact Us

If you need customization or are having any trouble using this hook, please contact our team and we’d be happy to assist you.