Form submits but results not showing

I am trying to write my first plugin based on code I picked up from around the web. The plugin installs and activates and has a page with a form. When I click the submit button on the form the page reloads. But the code handling the form is supposed to respond with a success or failure message in the url. It doesn’t do that. I am not seeing any errors. There are three files. The main file, a class file that has the form and a function file that has the form handling code. Would someone point out the mistake, please?

/**
Plugin Name: My Viewer
**/
/*** MAIN PAGE ***/

add_action( 'admin_menu' , 'My_viewer');

function My_viewer(){
    $page_title = 'My_viewer';
    $menu_title = 'My_viewer';
    $capability = 'manage_options';
    $menu_slug  = 'my_viewer';
    $function   = 'my_functions';

    add_menu_page( $page_title, $menu_title, $capability, $menu_slug, $function );
    add_submenu_page( $menu_slug, $page_title, 'Panel', 'manage_options', 'my-panel-submenu-page', 'my_panel_page' );
}

function my_functions(){
   require_once plugin_dir_path( __FILE__ ) . '/includes/my_functions.php';
}
function my_panel_page() {
    require_once dirname( __FILE__ ) . '/includes/class-my-class.php';
    $page = new My_class( plugin_basename( __FILE__ ) );

?>
  <div class="wrap">
   <h1><?php esc_html_e( 'Main Panel', 'access-log-viewer' ); ?></h1>
   <?php $page->DisplayPanel(); ?>
  </div>
<?php
}


/*** FUNCTIONS FILE ***/

function traitement_formulaire_don_cagnotte() {
 if ( ! isset( $_POST['cagnote-don-envoi'] ) || ! isset( $_POST['cagnotte-verif'] ) )  {
  return;
 }

 if ( ! wp_verify_nonce( $_POST['cagnotte-verif'], 'faire-don' ) ) {
  return;
 }

 $don = intval( $_POST['don'] );
 $url = wp_get_referer();

 // Donation amount is too low.
 if ( $don < 0 ) {
  $url = add_query_arg( 'erreur', 'radin', wp_get_referer() );

 // Donation amount is too high.
 } elseif ( $don > 10000 ) {
  $url = add_query_arg( 'erreur', 'trop', wp_get_referer() );

 // Everything's OK, let's do the work...
 } else {
  $cagnotte_actuelle = intval( get_option( 'valeur_cagnotte', 0 ) );
  update_option( 'valeur_cagnotte', $cagnotte_actuelle + $don );
  $url = add_query_arg( 'success', 1, wp_get_referer() );
 }

 // Redirect user back to the form, with an error or success marker in $_GET.
 wp_safe_redirect( $url );
 exit();
}
add_action( 'template_redirect', 'traitement_formulaire_don_cagnotte' );

/*** CLASS FILE ***/

class My_class {
  public function __construct( $plugin_basename ) {
  }
  
  public function DisplayPanel() {
    if ( isset( $_GET['erreur'] ) ) {
     $error = sanitize_title( $_GET['erreur'] );

     switch ( $error ) {
      case 'radin' :
       $message = __( 'We need a positive amount.', 'msk' );
       break;

      case 'trop' :
       $message = __( 'Thanks, but we do not need that much money.', 'msk' );
       break;

      default :
       $message = __( 'Something went wrong.', 'msk' );
       break;
     }

     printf( '<div class="error"><p>%1$s</p></div>', esc_html( $message ) );
    }
    ?>
    <form action="<?php echo esc_url( $_SERVER['REQUEST_URI'] ); ?>" method="POST" class="comment-form">
     <?php wp_nonce_field( 'faire-don', 'cagnotte-verif' ); ?>

     <div>
      <label for="don"><?php _e( 'Amount donation' ); ?></label>
      <input id="don" type="number" name="don" value="5" />
     </div>

     <input id="submit" type="submit" name="cagnote-don-envoi" id="submit" class="submit" value="<?php esc_attr_e( 'Submit', 'msk' ); ?>" />
    </form>
      <?php
      ?> <pre> <?php
    print_r($_GET);
    ?> </pre> <?php
  }
}

• This topic was modified 1 year, 11 months ago by wpusrpt.