selecting checked radio inputs and filtering by html data attributes

by Akram kamal

HTML

<input type=checkbox data-answer="correctanswer">
<input type=checkbox data-answer="correctanswer">
<input type=checkbox data-answer="correctanswer">
<input type=checkbox data-answer="correctanswer">
<input type=checkbox data-answer="correctanswer">
<input type=checkbox data-answer="correctanswer">
<input type=checkbox data-answer="correctanswer">

<button>
  check
</button>

JavaScript

$("button").click(function() {
  var correctAnsswers = $(":checked[data-answer='correctanswer']")
  alert(correctAnsswers.length)
})