Question

This question is similar to this one (but not exact):
Count immediate child div elements using jQuery

I have a bunch of lists that represent christmas presents for different people.
As an example, this is a list of presents for one person. Note that new people can be added

<ul id = "presents">
<li id = "person1" >
<ul id = "presentsforperson1">
<li id = "present1" >
<ul id = "present1info">
<li> Present 1 </li>
<li> A New Pair of Shoes </li>
<li> $19.99 </li>
</ul>
</li>
<!-- More presents for person 1 can be added here dynamically-->
</ul>
</li>
<!-- More people can be added here -->
</ul>

Unlike the question posted, I have the object presentsforperson1 in a variable called drop (droppable). I was wondering what the correct syntax is for finding the number of presents person 1 has (in this case 1) with this variable?

This is what I have tried so far:

 var numberofPresents = $(drop + "ul > li").length; //drop holds li#presentsforperson1 .droppable
 var numberofPresents = $(dropid + "ul > li").length; //dropID is $(drop).attr("id");

Answer 1

If the person id is the id of the ul containing their presents then simply:

$('#personId > li').length

will do it.

Update

Or if the id is in a variable:

$('#' + personId).children('ul').length

You obviously could append the child selector to the selector string eg:

$('#' + personId + ' > ul').length

But personally I find the version with the .children call more readable.