This piece of code appears in a js script I have been asked to modify - I'm not sure why it is written in this way, it doesn't make sense to me.
Can anyone help explain what it is doing, and if it can be simplified to be a little more meaningful?
var unformathtml = $(this).text();
if(unformathtml.trim().length>showChar) {
$(this).parent().parent().parent().parent().parent().find('.comment-footer').fadeOut();
}
Lets' pretend we have a DOM like this:
<parent-5>
<target-element>Content</target-element>
<parent-4>
<parent-3>
<parent-2>
<parent-1>
<focused-element>Some Text</focused-element>
</parent-1>
</parent-2>
</parent-3>
</parent-4>
</parent-5>
What this code is saying is "if the text inside of <focused-element> has more characters than showChar then fade out <target-element>.
A better way of doing this would be to give <parent-5> some kind of identifier, which could be an ID or a class, and target that instead of the repeated .parent() call.
Here's an example which showcases the idea:
$('#oldMethod').click(function() {
$(this)
.parent()
.parent()
.parent()
.parent()
.parent()
.find('.comment-footer')
.toggleClass('red');
});
$('#newMethod').click(function() {
$(this)
.closest('.comment-container')
.find('.comment-footer')
.toggleClass('red');
});.red {
color: #F00;
}<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="comment-container">
<div>
<div>
<div>
<div>
<button id="oldMethod">Old</button>
<button id="newMethod">New</button>
</div>
</div>
</div>
</div>
<div class="comment-footer">Footer</div>
</div>Wow, that really doesn't make much sense. It is doing this:
1) Getting the raw contents out of an element 2) Checking to see if it is longer than a certain length 3) If so, fading out another element on the page
The parents() thing is very error-prone. It is going up a very precise number of levels in the HTML tree and then descending downwards to find an element with a class of '.comment-footer'. As a result a slight rearrangement of either element in the DOM might result in the code no longer working, because it can't find the specified element.
What you want is to find the tag-to-hide more directly. Ideally, the element-to-hide and the element-that-decides-to-hide would be next to eachother in the DOM (i.e. the element being hidden would be a child or sibling of the element that decides whether or not to hide it). This makes it very easy for the one to find the other. If that isn't possible, your next best bet would be to simply assign an id to the element you are trying to hide and then select on that id directly:
var unformathtml = $(this).text();
if(unformathtml.trim().length>showChar) {
$('#to_hide').fadeOut();
}
As a quick aside, .text() is used (instead of .html()), because the former removes any HTML tags. This way you are measuring the amount of "actual" text inside $(this) to determine whether or not you want to hide said element. So that part is probably fine.
showCharis greated than the ones in the elementthis, it will hide with an animation the.comment-footer..parent()can be reduced to a.closest()is you have something to identify the ancestor tag, or a.parents().eq(4)which is not so clean and good performance wise. As for what it does, it simply hide (with a fading animation) something if the number of chars is higher than something...