Choose the last id in div block

[terrea]

There's a structure.

<div id="block">
  <p id="p_1">text</p>
  <p id="p_2">text</p>
  <p id="p_3">text</p>
  <p id="p_4">text</p>
  ....
</div>

We've got to pull out the last id in the example of p-4, how do we do it?

[simrah]

.last() - Reset the last element from all the chosen ones.

http://jquery.page2page.ru/index.php5/%D0%9F%D0%BE%D0%B8%D1%81%D0%BA_%D0%BF%D0%BE%D1%81%D0%BB%D0%B5%D0%B4%D0%BD%D0%B5%D0%B3%D0%BE_%D1%8D%D0%BB%D0%B5%D0%BC%D0%B5%D0%BD%D1%82%D0%B0_%D0%B2_%D0%BD%D0%B0%D0%B1%D0%BE%D1%80%D0%B5

https://api.jquery.com/last/

alert($('#block p').last().attr('id'));

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<div id="block">
  <p id="p_1">text</p>
  <p id="p_2">text</p>
  <p id="p_3">text</p>
  <p id="p_4">text</p>
</div>

Another option:

:last-child - Consistent with all elements that are the last daughters of the parent.

https://api.jquery.com/last-child-selector/

http://jquery-docs.ru/Selectors/lastChild/

alert($('#block p:last-child').attr('id'));

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<div id="block">
      <p id="p_1">text</p>
      <p id="p_2">text</p>
      <p id="p_3">text</p>
      <p id="p_4">text</p>
    </div>