Question

The mind boggles – my colleague sent me this script – I am sure I overlook something simple

http://jsfiddle.net/mplungjan/j4m62/

which for some reason I cannot figure out, checks all three checkboxes regardless of which I click – I would expect only the first two to be checked on click of either of the first two and the third to be checked on its own

HTML:

<input class="check-all" name="checkbox[]"  id="checkbox1" type="checkbox" value="on"/><label for="checkbox1">Check 1&2</label><br/>

<input class="check-allfeatured" name="checkbox[]"  id="checkbox2"  type="checkbox" value="on"/><label for="checkbox2">Check 1&2</label><br/>

<input class="check-alldel" name="deleteids[]"  id="deleteids1"  type="checkbox" value="on"/><label for="deleteids1">Check this only</label>

JavaScript:

$(document).ready(function(){
  $('.check-all:checkbox').click(function(event) {
      var group = 'input:checkbox[name=' + $(this).attr('name') + ']';
      console.log(group+':'+event.target.checked);
      $(group).each(function(){
          $(this).attr("checked",event.target.checked);
      });
  });

  $('.check-alldel:checkbox').click(function(event) {
      var group = 'input:checkbox[name=' + $(this).attr('name') + ']';
      console.log(group+':'+event.target.checked);
      $(group).each(function(){
          $(this).attr("checked",event.target.checked);
      });
   });

  $('.check-allfeatured:checkbox').click(function(event) {
      var group = 'input:checkbox[name=' + $(this).attr('name') + ']';
      console.log(group+':'+event.target.checked);
      $(group).each(function(){
          $(this).attr("checked",event.target.checked);
      });
  });
});

Answer 1

While not pretty, the corrected version is here: http://jsfiddle.net/j4m62/8/

Your problem was that you were not putting quotes around the names of your checkbox name assertion.

Change:

var group = 'input:checkbox[name=' + $(this).attr('name') + ']';

into:

var group = 'input:checkbox[name="' + $(this).attr('name') + '"]';

and you will get the behavior you are expecting. But you really have a lot of duplicated code so you should probably refactor since you are performing the same operation regardless of the checkbox clicked. Check this out.

Thanks @limelights for pointing out that I forgot to explicitly pass event in. Updated link.