Html程序  |  81行  |  2.72 KB

<html>
<head>
  <title>Empty and nested optgroup elements</title>
</head>

<body>

<select>
  <!-- A div here is invalid. However, both IE and Firefox will walk into it
       and enumerate the elements inside. -->
  <div>
    <option value="1">Item one</option>

    <!-- this group has no children. We /should/ render it because that matches
         IE and FireFox. -->
    <optgroup label="Group one"></optgroup>

    <!-- this group has a text node child. It should render the same as group one. -->
    <optgroup label="Group two"> </optgroup>

    <!-- for an optgroup without a label, IE will show an empty, unselectable row.
         Firefox doesn't show it. We /do/ show it because someone might be using
         it as a spacer. -->
    <!-- Additionally, this has been updated to test the crash fixed in
         https://bugs.webkit.org/show_bug.cgi?id=26656. When setting the
         font-size in the <optgroup> to extra large, opening the select element
         must not leave any unpainted areas of overlapping text. -->
    <optgroup style="font-size: x-large;">
      <option value="2">Item inside an optgroup without a label</option>
    </optgroup>

    <!-- for an optgroup with an empty label, IE will show an empty,
         unselectable row.  Firefox doesn't show it. We /do/ show it because
         someone might be using it as a spacer. -->
    <optgroup label="">
      <option value="3">Item inside an optgroup with an empty label</option>
    </optgroup>

    <div>
      <option value="4"></option>
      <optgroup label="Group three">
        <option value="5">Item two</option>
        <!-- nested groups are disallowed by the spec, but IE and Firefox will
             flatten the tree. We should match them. -->
        <optgroup label="Nested group 1"></optgroup>
        <optgroup label="Nested group 2">
          <optgroup label="Nested group 3">
              <option value="6">Item three</option>
          </optgroup>
        </optgroup>
      </optgroup>
    </div>
    <option value="7">Item four</option>
  </div>
</select>

<p>Click on the select element above. When it drops down you should see the following items in the list:</p>

<ul>
  <li>Item one</li>
  <li><b>Group one</b></li>
  <li><b>Group two</b></li>
  <li><i>(unselectable, empty row)</i></li>
  <li>Item inside an optgroup without a label</li>
  <li><i>(unselectable, empty row)</i></li>
  <li>Item inside an optgroup with an empty label</li>
  <li><i>(selectable, empty row)</i></li>
  <li><b>Group three</b></li>
  <li>Item two</li>
  <li><b>Nested group 1</b></li>
  <li><b>Nested group 2</b></li>
  <li><b>Nested group 3</b></li>
  <li>Item three</li>
  <li>Item four</li>
</ul>

<p>The text of the rows of the dropdown must not overlap each other.</p>

</body>
</html>