Check if an element with a specific class is within the body

Question

I would like to show a span element, if a div element with a specific class is within the body and hide the span, if the div with the specific class isn't anymore within the body. So I tried to solve this with the jQuery function has(). It works for the first time as expected. But when I rename the specific class of the div to specific-element-1 and reload it, the span is still visible. What am I doing wrong? Here the codepan, so you can easy change the class name to check it: https://codepen.io/STWebtastic/pen/VyObKM

PS: I also tried to solve this with the jQuery functions after() and children() in case of has(), but didn't work. Hope this is clear enough.

$(document).ready(function() {
  if ($('body').has('.specific-element')) {
    $('.showme').show();
  } else {
    $('.showme').hide();
  }
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>

<body>
  <div class="specific-element"></div>
  <span class="showme">Hello World!</span>
</body>

Check length property `if($('.specific-element').length > 0)` — Satpal, Jan 24 '18 at 10:39
`has()` returns a jQuery object, not a boolean, so you need to check the `length` property to see if any elements were matched. — Rory McCrossan, Jan 24 '18 at 10:40
Also in the jquery faq: https://learn.jquery.com/using-jquery-core/faq/how-do-i-test-whether-an-element-exists/ — freedomn-m, Jan 24 '18 at 11:02

kiranvj · Accepted Answer · 2018-01-24T10:42:39.110

2

Try this

$(document).ready(function() {
  if ($('body .specific-element').length) {
    $('.showme').show();
  } else {
    $('.showme').hide();
  }
});

Updated pen here

edited Jan 24 '18 at 10:42

answered Jan 24 '18 at 10:40

kiranvj

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Perfect, it works. :) Is this also best-practice? Cheers – webta.st.ic Jan 24 '18 at 10:42
1

Best practice? not sure, but definitely not a bad way ! – kiranvj Jan 24 '18 at 10:45
Given the number of upvotes on this answer, seems to be a good way to go: https://stackoverflow.com/a/587408/2181514 (it's also in the jquery faq) – freedomn-m Jan 24 '18 at 11:01

Check if an element with a specific class is within the body

1 Answers1