Jquery - add data with to element and get element by added data

Question

Can i get and element by data added with jquery? For Example

   function first() {
    var modal_body = $('.modal-body');
    modal_body.data('id',4)
   }
   
   function second() {
    var modal_body = $('.modalbody[data-id=4]');
   }
    
   

I've already tried this example, but it doesn't work because the element doesn't have data-id. Jquery saves data internally and creates an empty object called $.cache.

Is there any posibility to get the element, which contains data added with Jquery?

Answer 1

Unfortunately, no.

As you said, the data properties are added internally by jQuery. The only way to achieve what you want is to set attributes directly:

   function first() {
     var modal_body = $('.modal-body');
     modal_body.attr('data-id',4)
   }

   function second() {
    var modal_body = $('.modal-body[data-id=4]'); // note: fixed .modalbody to .modal-body
   }

Which makes it available as .data('id') as well.

Another alternative would be to use .filter():

   function first() {
     var modal_body = $('.modal-body');
     modal_body.data('id',4)
   }
   function second() {
    var modal_body = $('.modal-body').filter(function () {
      return $(this).data('id') === 4;
    });
   }

Demo below.

(() => {
  var modal_body = $('div.modal-body');
  modal_body.attr('data-id', 4)

  console.log('found using attr:', $('.modal-body[data-id=4]').length);
})();

(() => {
  var modal_body = $('span.modal-body');
  modal_body.data('id', 4)

  console.log('found using filter:', $('span.modal-body').filter(function() {
    return $(this).data('id') === 4;
  }).length);
})();

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

<div class="modal-body">modal-body</div>

<span class="modal-body">modal-body</span>

Answer 2

Not with a single selector, but certainly using .filter():

$("#x").data("data", "a");
$("#y").data("data", 4);

var x2 = $("div").filter(function() {
    return $(this).data("data") != null;
});

var y4 = $("div").filter(function() {
    return $(this).data("data") === 4;
});

console.log("Divs:", $("div").length, "With ID:", x2.length, "With id==4:", y4.length);
x2.addClass("box");
y4.addClass("box4");

div { border: 1px solid #CCC; }
.box { border: 1px solid green; }
.box4 { border: 1px solid red; }

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div id='x'>x</div>
<div id='y'>y</div>
<div id='z'>y</div>

Update: check for explicit data value, not just any