Help me pls

[Elan]

Why does this not work?

 

var i;
for (i = 0; i <= correctEls.length; i++) {
  correctEls[j].addEventListener("click", function() {
    whenCorrectClicked(i);
  });
  i++;
}
 

Here is the full site for more info

https://jsfiddle.net/elan5000/v7obgfny/256/

[justsomeguy]

Because by the time that event handler runs, i is set to something else.  It doesn't use the value that i had when you assigned the event handler, it uses the current value of i, whatever that is.  You can use a closure to pass i as a new variable and use the value of that instead.

var i;
for (i = 0; i <= correctEls.length; i++) {
  correctEls[j].addEventListener("click", (function(idx) {
    return function() {
      whenCorrectClicked(idx);
    }
  })(i));
  i++;
}

Now that makes an anonymous function that executes immediately (IIFE), which you pass the value of i, and inside the function it uses idx for the parameter.  The IIFE returns a function which uses the value of idx, that returned function gets assigned as the click handler.