Altering the attachments for E-mails via PHP code for WordPress

If you have a form with a dropdown and you wish to attach a specific file to the E-mails based on the selected dropdown item you can use the below code to achieve this.

Place below code in your child theme functions.php file

You can use the super_before_sending_email_attachments_filter for admin E-mails and the super_before_sending_email_confirm_attachments_filter for Confirmation E-mails.

In the below code make sure to replace the your_dropdown_name with the field name of your dropdown element. Also make sure to correctly map the dropdown values with the corresponding file ID's that are stored on your WordPress site. In the below example they are mapped to the dropdown item value option1, option2 and option3.

add_filter('super_before_sending_email_attachments_filter', 'f4d_custom_attach_file_based_on_dropdown', 10, 2);
function f4d_custom_attach_file_based_on_dropdown($attachments, $atts) {
    // Retrieve the form data
    $form_data = $atts['data'];
    
    // Replace 'your_dropdown_name' with the actual name or ID of your dropdown field
    $dropdown_name = 'your_dropdown_name';
    
    // Ensure the dropdown field exists
    if (isset($form_data[$dropdown_name])) {
        $dropdown_value = $form_data[$dropdown_name]['value'];
        
        // Define your attachments based on dropdown value
        $attachments_map = array(
            'option1' => 1234, // ID of the attachment in WP
            'option2' => 1235, // ID of the attachment in WP
            'option3' => 1236  // ID of the attachment in WP
        );

        // Check if the selected value has an attachment
        if (isset($attachments_map[$dropdown_value])) {
            // Add the attachment to the attachments array
            $attachments[$dropdown_value.'.pdf'] = wp_get_attachment_url($attachments_map[$dropdown_value]);
        }
    }
    return $attachments;
}