How can I get, using jquery, the id of the first div with class: post (367), in the following HTML code:

<div id="own-posts">
  <span class="title">Me</span>    
  <div class="posts_container">
    <div class="post"></div>  

    <div id="367" class="post"></div>
    <div id="365" class="post"></div>
    <div id="345" class="post"></div>
    <div id="343" class="post"></div>

  </div>

</div>

Among the solutions I tried:

$('#own-posts').children()[1].children()[1].attr('id');

How can I get, using jquery, the id of the first div with class: post (367), in the following HTML code:

<div id="own-posts">
  <span class="title">Me</span>    
  <div class="posts_container">
    <div class="post"></div>  

    <div id="367" class="post"></div>
    <div id="365" class="post"></div>
    <div id="345" class="post"></div>
    <div id="343" class="post"></div>

  </div>

</div>

Among the solutions I tried:

$('#own-posts').children()[1].children()[1].attr('id');

• javascript
• jquery
• html

• 3 It is not valid to have an ID starting with a number (except in HTML5), older browser may plain of problems. – Niet the Dark Absol Commented Sep 28, 2013 at 11:15
• @Kolink Thank you for your important remark, I will take it into consideration in future. What about having number in data-attribute, is it causing the same problem? – Adib Aroui Commented Sep 28, 2013 at 11:17
• @whitelettersandblankspaces No, it's not! Following Kolink's ment, even it's pletly valid to start ID with a number in HTML5, CSS still doesn't like it. So you should follow Kolink's advice – A. Wolff Commented Sep 28, 2013 at 11:22
• @whitelettersandblankspaces I like to use data-id when I'm storing an ID number. In jQuery you can access it with .data("id") if you want (I don't use jQuery myself, so I just use .getAttribute("data-id")) – Niet the Dark Absol Commented Sep 28, 2013 at 11:23
• 1 @whitelettersandblankspaces you should prefix IDs if using ID attribute, you shouldn't have to prefix IDs if using data-id attribute – A. Wolff Commented Sep 28, 2013 at 11:31

3 Answers 3

The first .post element doesn't have an ID, so I guess you mean the first .post element that actually has an ID attribute :

var id = $('#own-posts .post[id]:first').prop('id');

FIDDLE

$('#own-posts .post:first').prop('id'); works if all divs with that class have a id.

Otherwise if the pattern is the first div.post does not have id, but the second does you can use:

$('#own-posts .post').eq(1).prop('id');

I used .prop() because of this

Try

$('#own-posts .post').eq(1).prop('id');

DEMO