Contact Form 7: Add Custom Data Providers to Select Elements/Tags

wordpress, wpcf7, select, values, database, lists, callback, programmatically

Every WordPress Power User knows the awesome Contact Form 7 plugin. It is (one of) the best plugins to create custom forms without any PHP knowledge – especially useful for endusers/customers.

But sometimes you need to create select list values programmatically. Unfortunately the Contact Form 7 Docs are very poor in matter of advanced use cases including the build-in filter hooks.

WPCF7 Form Editor#

Just add a unique name to the data attribute – in this example my.data.provider. This allows you to match the element within the filter hook!

<p>
<label> My List
    [select mylist include_blank data:my.data.provider]
</label>
</p>

Filter Hook#

Roll the drums…the magical filter hook wpcf7_form_tag_data_option allows you to alter the options list and add options/values to the select list within a simple callback

add_filter('wpcf7_form_tag_data_option', function($n, $options, $args){
    // special data provider tag found ?
    if (in_array('my.data.provider', $options)){
        return get_my_value_list();
    }

    // default - do not apply any changes within the options
    return null;
}, 10, 3);

Well, thats it!

You may have noticed, that normal users (especially Author’s and Contributor’s) are not allowed to use all kind of HTML Tags and related Attributes.

Those elements got removed by the WordPress buil-in KSES Filter – and it’s a very useful feature in matter of security to prevent html-code-injection.

But sometimes it is required to enable some additional html tags and/or attributes. You can modify the list of allowed html tags and attributes by appling a custom filter:

The Filter#

Example how to allow EnlighterJS related attributes for pre and code tags

function ksesAllowHtmlCodeAttributes($data, $context){
    // only apply filter on post-context
    if ($context === 'post'){

        // list of all available enlighterjs attributes
        $allowedAttributes = array(
            'data-enlighter-language' => true,
            'data-enlighter-theme' => true,
            'data-enlighter-group' => true,
            'data-enlighter-title' => true,
            'data-enlighter-linenumbers' => true,
            'data-enlighter-highlight' => true,
            'data-enlighter-lineoffset' => true
        );

        // apply to pre and code tags
        $data['pre'] = array_merge($data['pre'], $allowedAttributes);
        $data['code'] = array_merge($data['code'], $allowedAttributes);
    }

    return $data;
}

// add the filter function (2 arguments and priority 100)
add_filter('wp_kses_allowed_html', 'ksesAllowHtmlCodeAttributes', 100, 2);

 

 

 

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Add Links to WordPress Plugin Page (Metadata Row)

Additional News/Update or Settings Links

Sometime you want to add special links directly to the plugin-page. For example, you can enable an easy access to the plugin’s settings-page or to related docs/resources. All the magic is done within the plugin_row_meta hook.

It’s important to check which plugin is currently processed (there are no plugin/namespace specific hooks). Therefore you have to check which plugin-(main)file is selected: if ($file == 'enlighter/Enlighter.php'){

Additional links can be added to the $links array including I18n support.

Appearance#

additional_plugin_links

How it’s done#

// add links
add_filter('plugin_row_meta', 'addPluginPageLinks', 10, 2);

// links on the plugin page
function addPluginPageLinks($links, $file){
  // current plugin ?
  if ($file == 'enlighter/Enlighter.php'){
    $links[] = '<a href="'.admin_url('options-general.php?page='.plugin_basename(__FILE__)).'">'.__('Settings', 'enlighter').'</a>';
    $links[] = '<a href="https://twitter.com/andidittrich">'.__('News & Updates', 'enlighter').'</a>';
  }
  
  return $links;
}

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