jquery checked and unchecked events

Question

I have a problem here with the following code

$('.paron').change(function() {
   if($(this).is(":checked")) {
          var moduleid = <?php echo $moduleid; ?>;
                var studentid = $(this).attr('id');
                var weeknum = <?php echo $weeknum; ?>;

                undisableTxt(studentid);

             }
       });

So I take the id of a certain tr which has an input and i send it to a function. All good till now. But this is happening when the user check the input [checkbox] when he UNCHECK, how can i have the id to send it to another function???

I've tried the following but no luck

   $('.paron').change(function() {
if($(this).is(":checked")) {
     var moduleid = <?php echo $moduleid; ?>;
     var studentid = $(this).attr('id');
     var weeknum = <?php echo $weeknum; ?>;

             undisableTxt(studentid);

      } else {
        disableTxt(studentid); //error for undefined variable student id.
      }
  });

So i get an error for undefined studentid. FYI each row has another id.

Steven Lacks · Accepted Answer · 2016-11-22 22:26:14Z

1

The variable 'studentId' doesn't exist in your else block. Also you shouldn't define variables with var in blocks, because var doesn't scope variables at the block level, use let or const for that. I also set $this, to save going back and forth into the DOM for performance.

in jQuery you would do it like this.

$('.paron').change(function() {
  const $this = $(this);  
  const studentid = $this.attr('id');

  if($this.is(":checked")) {
    // removed for brevity, but using let or const
    undisableTxt(studentid);
  } else {
    disableTxt(studentid); 
  }
});

edited Nov 22, 2016 at 22:26

answered Nov 22, 2016 at 22:23

Steven Lacks

9046 silver badges13 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Konstantinos Natsios Over a year ago

I also found out another workaround with closest but yours its better! Thanks a lot!! gonna accept it when system let me to!

Steven Lacks Over a year ago

Thanks, hopefully, my other comments/changes don't seem rude or know-it-all, I just wanted to make the example best as I could.

Konstantinos Natsios Over a year ago

I'm newbie to jquery and this about const and let helps me a lot cause i've seen let only in swift and i know it has great performance !! much appreciated :D

Collectives™ on Stack Overflow

jquery checked and unchecked events

1 Answer 1

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related