Button to clear transients

Question

I would like to add a button on the admin page to clear the transients I use.

See my code below:

<?php
// If this file is called directly, abort.
defined('ABSPATH') or exit();

/*
 * Generate the admin page
 */
function advanza_direct_plugin_settings() {
    $form = new advanza_direct_form;
    $plugin_settings = new advanza_direct_plugin;
    // For debugging
    // $form->debug();
    // $plugin_settings->debug();
    ?>
    <div class="wrap">
        <img src="<?php echo plugin_dir_url( __FILE__ ) . '/assets/img/advanza-direct.png'; ?>" id="advanza-direct-logo">
        <h1><?php echo __('Advanza Direct form', 'advanza_form_shortcode');?></h1>
        <p>Advanza Direct form settings, enter your specific settings below:</p>

    <?php if (isset($_GET['settings-updated']) && $_GET['settings-updated'] == 'true'):
        echo '<div id="setting-error-settings_updated" class="updated settings-error">
        <p><strong>' . __("Settings saved", "advanza_form_shortcode") . '</strong></p>
     </div>';
    endif;
    ?>
    <form method="post" action="options.php">
        <?php settings_fields('advanza_direct_plugin_settings'); ?>
        <?php do_settings_sections('advanza_direct_plugin_settings'); ?>
        <table id="advanza-direct-form-settings" class="form-table form-settings">
            <tr valign="top">
                <th scope="row"><?php echo __('Form to:', 'advanza_direct_form_to');?></th>
                <td>
                    <input type="text" name="advanza_direct_form_to" value="<?php echo get_option('advanza_direct_form_to'); ?>" placeholder="[email protected]">
                </td>
            </tr>
            <tr valign="top">
                <th scope="row"><?php echo __('Form subject:', 'advanza_direct_form_subject');?></th>
                <td>
                    <input type="text" name="advanza_direct_form_subject" value="<?php echo $form->get_subject; ?>" placeholder="Aanmelding professional"> - yourdomain.com (automatic)
                </td>
            </tr>
        </table>
        <?php submit_button(); ?>
        <h2>How to use the shortcode?</h2>
        <p>Use <input id="shortcode1" value="[advanza-direct-form]" size="18">
            <button class="shortcode" data-clipboard-target="#shortcode1">
                <img src="<?php echo plugins_url('/assets/img/clippy.svg', __FILE__);?>" width="14" alt="Copy to clipboard">
            </button> in your pages, posts and widgets. Use the shortcode whenever you want to use the Advanza form.<br>
        Or you could use the Advanza form widget functionality. To use the widget, simply go to:<strong> > Appearance > Widgets</strong></p>

        <br><br>

        <h2>Advanza Direct terms of service and privacy policy</h2>
        <table id="advanza-direct-plugin-settings" class="form-table form-settings">
            <tr valign="top">
                <th scope="row"><?php echo __('Terms of service URL:', 'advanza_direct_terms_of_service');?></th>
                <td>
                    <input type="text" name="advanza_direct_terms_of_service" value="<?php echo get_option('advanza_direct_terms_of_service'); ?>" placeholder="https://advanzadirect.nl/advanza-direct/terms-of-service.html">
                </td>
            </tr>
            <tr valign="top">
                <th scope="row"><?php echo __('Privacy policy URL:', 'advanza_direct_privacy_policy');?></th>
                <td>
                    <input type="text" name="advanza_direct_privacy_policy" value="<?php echo get_option('advanza_direct_privacy_policy'); ?>" placeholder="https://advanzadirect.nl/advanza-direct/privacy-policy.html">
                </td>
            </tr>
        </table>
        <?php submit_button(); ?>

        <h2>Shortcode for Advanza terms of service and privacy policy</h2>
        <p><strong>Terms of service shortcode:</strong> <input id="shortcode2" value="[advanza-direct-terms-of-service]" size="30">
            <button class="shortcode" data-clipboard-target="#shortcode2">
                <img src="<?php echo plugins_url('/assets/img/clippy.svg', __FILE__);?>" width="14" alt="Copy to clipboard">
            </button>
        </p>
        <p>
            <strong>Privacy policy shortcode:</strong> <input id="shortcode3" value="[advanza-direct-privacy-policy]" size="28">
                <button class="shortcode" data-clipboard-target="#shortcode3">
                    <img src="<?php echo plugins_url('/assets/img/clippy.svg', __FILE__);?>" width="14" alt="Copy to clipboard">
                </button>
        </p>
    </form>

    <script>
    jQuery(document).ready(function( $ ) {
        // For debugging
        // console.log('jQuery is ready!');

        $('.shortcode').click(function( event ) {
            event.preventDefault();
        });

        // Tooltip
        $('.shortcode').tooltip({
            trigger: 'click',
            placement: 'top'
        });

        function setTooltip(btn, message) {
            $(btn).tooltip('hide')
            .attr('data-original-title', message)
            .tooltip('show');
        }

        function hideTooltip(btn) {
            setTimeout(function() {
                $(btn).tooltip('hide');
            }, 500);
        }

        // Clipboard
        var clipboard = new ClipboardJS('.shortcode');

        clipboard.on('success', function(e) {
            // console.log(e); // For debugging
            setTooltip(e.trigger, 'Copied!');
            hideTooltip(e.trigger);
        });

        clipboard.on('error', function(e) {
            // console.log(e); // For debugging
            setTooltip(e.trigger, 'Failed!');
            hideTooltip(e.trigger);
        });


    });
    </script>

</div>
<?php }

Answer 1

I have managed to do the following. I made a clear cache button:

function advanza_direct_plugin_delete_transients() {
  delete_transient( 'advanza_direct_terms_of_service' );
  delete_transient( 'advanza_direct_privacy_policy' );
  // at the end redirect to target page
  exit( wp_redirect( admin_url( 'admin.php?page=advanza-direct-plugin-settings' ) ) );
}
add_action( 'admin_post_advanza_direct_plugin_delete_transients', 'advanza_direct_plugin_delete_transients' );

I put this where I have my admin logic:

<form action="<?php echo admin_url('admin-post.php'); ?>" method="post">
        <input type="hidden" name="action" value="advanza_direct_plugin_delete_transients">
        <?php submit_button( 'Clear cache', 'delete', '', false ); ?>
</form>