title: Preg replace - reg ex needed
body: <p>Looking for a reg ex to null (empty) the string if it any contains the bad word..</p>
  
  <pre><code>    $string1 = "Ihatestackoverflow";
      $string2 = "I HaTe sackoverflow";
      $string3 = "1HaTestackoverflow";
  
      $badword = "hate";
  
  # result
  # string1 = "";
  # string2 = "";
  # string3 = "";
  </code></pre>