thub-link">
              <img src="../content/img/github.png" class="normal" />
              <img src="../content/img/github-blue.png" class="hover" />
            </a>
          <p>Returns if the string is null or empty or completely whitespace</p>



        </td>
      </tr>
      <tr>
        <td class="member-name">

          <code onmouseout="hideTip(event, '609', 609)" onmouseover="showTip(event, '609', 609)">
            isUmlaut c
          </code>
          <div class="tip" id="609">
          