How can I also add class to the last list for the second list block in IE?

I have 2 list and i want to add a class ="last" to the list item 5 for both. they seem to work fine on firefox. it add green to both list item 5.

But in IE开发者_C百科7 it adds only the first list item 5, not the second

How can I also add class last it to the second list block as well for IE?

.last { background-color: green; }

with:

jQuery(document).ready(function() {
  // Add first and last menu item classes
  $('ul.menu li:first-child').addClass('first_item');
  $('#menu > li:last-child').addClass('last');
});

and:

<ul id="menu">
  <li>list item 1</li>
  <li>list item 2</li>
  <li>list item 3</li>
  <li>list item 4</li>
  <li>list item 5</li>
</ul>
<br />

<ul id="menu">
  <li>list item 1</li>
  <li>list item 2</li>
  <li>list item 3</li>
  <li>list item 4</li>
  <li>list item 5</li>
</ul>
<br />

The problem is you're using the id menu twice. That's not allowed and why it isn't working. Give it a class instead:

<ul class="menu">
  <li>list item 1</li>
  <li>list item 2</li>
  <li>list item 3</li>
  <li>list item 4</li>
  <li>list item 5</li>
</ul>

with:

$(function() {
  $("ul.menu > li:last-child").addClass("last");
});