Question

Please help me out with the following code. I don’t understand it. I have to use a snippet like this in my project.

$('strong', this) <- this part is not clear to me at all.

Please be kind enough to explain the whole code line by line if possible.

<ul>
   <li><strong>list</strong> item 1 -
      one strong tag
   </li>
   <li><strong>list</strong> item <strong>2</strong> -
      two <span>strong tags</span>
   </li>
   <li>list item 3</li>
   <li>list item 4</li>
   <li>list item 5</li>
   <li>list item 6</li>
</ul>

JavaScript:

$('li').filter(function(index) {
  return $('strong', this).length == 1;
}).css('background-color', 'red');

Answer 1

$('strong', this) is jQuery selector with $(target, context) format.

According to your code:

this refers to li and $('strong', li) is searching a <strong> that within that li tag.

This statement can also be written as:

$(this).find('strong') and from jQuery library code you’ll see that:

$(target, context) format internally implement the

$(context).find(target) process.

For more see here.