从表号获取密码验证

[...document.querySelectorAll("#passwordTable td")].forEach(function(item) {
  item.addEventListener('click', function() {
    document.getElementById('pass').value += item.textContent.trim();

  })

})

td {
  cursor: pointer
}

td:hover {
  background: blue;
  zoom: 1.1;
  color: #fff;
}

<input type='password' id='pass'>
<table border="2" id="passwordTable">
  <tr>
    <td>1</td>
    <td>2</td>
    <td>3</td>
  </tr>
  <tr>
    <td>4</td>
    <td>5</td>
    <td>6</td>
  </tr>
  <tr>
    <td>7</td>
    <td>8</td>
    <td>9</td>
  </tr>
</table>