如何在WP_Widget上顯示錯誤

Question

如何在窗體，Flash或其他消息中顯示錯誤，指出他做錯了什麼？

的代碼是這樣的：

class My_Widget extends WP_Widget { 
    public function update($new_instance, $old_instance) { 
     if (!valid($new_instance)) 
      // How do I notify the user with a custom message 
      return false; 
     else 
      return $new_instance 
    } 
} 

我知道，返回false防止被保存的選項，但用戶卻不知道爲什麼。

Answer 1

試試這個，

public function update($new_instance, $old_instance) { 
    $old_instance['errors'] = array(); 
    if (!valid($new_instance)) { 
      $$old_instance['errors']['myfield'] = 'Custom error mesasage goes here'; 
     // How do I notify the user with a custom message 
     return false; 
     //return $old_instance; 
    } 
    else 
     return $new_instance 
} 

public function form($instance) { 
    $myfieldMsg = (isset($instance['errors']) && isset($instance['errors']['myfield'])) ? $instance['errors']['myfield']) : null; 
    echo $myfieldMsg; 
    ....