1431454 - Tutorial on JavaScript/Guide/Loops_and_iteration has incorrect JavaScript code

Status: RESOLVED WORKSFORME

(Developer Documentation Graveyard :: General, enhancement, P1)

Description

[Serge Boyko]

:: Developer Documentation Request

      Request Type: Correction
     Gecko Version: unspecified
 Technical Contact: 

:: Details

Hi,
My second message today.

In this page has a bug:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Loops_and_iteration

<script>
function howMany(selectObject) {
  var numberSelected = 0;
  for (var i = 0; i < selectObject.options.length; i++) {
    if (selectObject.options[i].selected) {
      numberSelected++;
    }
  }
  return numberSelected;
}

var btn = document.getElementById('btn');
btn.addEventListener('click', function() {
  alert('Number of options selected: ' + howMany(document.selectForm.musicTypes));
});
</script>

should be:

<script>
  var numberSelected = 0;

function howMany(selectObject) {
  for (var i = 0; i < selectObject.options.length; i++) {
    if (selectObject.options[i].selected) {
      numberSelected++;
    }
  }
  return numberSelected;
}

var btn = document.getElementById("btn");
btn.addEventListener("click", function(){
  alert('Выбрано элементов: ' + howMany(document.selectForm.musicTypes))
});
</script> 

P.S. 
  var numberSelected = 0; // should be out of function, if not, always the same number ('1') returns

Comment 1

[Florian Scholz (Open Web Docs)]

Hi, sorry for not coming back to you earlier.

I've checked both the English and the Russian documentation and it works correct for me. It is better to have the variable inside the function and not in the global scope.

Please reopen with more details on what is not working. Do you get any error message in the console?