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JavaScript

Posted by Christine Bogdan
Christine Bogdan
11,349 Points

Tried with a different approach and not working. Can anyone help?

Hi there,

so Treasure used the following code to prevent a download in case the checkbox is not checked. 

$pdfs.on("click", function(event) {
  if ($(":checked").length === 0) {
     event.preventDefault();
     alert("Please check the checkbox"); 
  }
});

I tried a different approach (see below), but it's not working. I get the alert box with the checkbox being checked or unchecked. 

$pdfs.on("click", function(event) {
  const $checked = $("input").checked
    if (!$checked) {
      event.preventDefault();
      alert("Please check the box");    
    }
});

Can anyone help?

1 Answer

Eric Butler
Eric Butler
33,512 Points

I think it is because $("input") returns an array/NodeList of all <input>s instead of a single instance, and the .checked property needs to be attached to a single instance. I just dumped your code into CodePen to try it out, and if you just make a slight tweak, it seems to work:

$pdfs.on("click", function(event) {
  const $checked = $("input")[0].checked // <-- specify that you only want to test the first (0-indexed) instance of <input> in the array of nodes matching $("input")
    if (!$checked) {
      event.preventDefault();
      alert("Please check the box");    
    }
});

When I did that, the alert popped up when the box was unchecked, and didn't when the box was checked. See if that works for you.

Christine Bogdan
Christine Bogdan
11,349 Points

Thanks!! That makes sense.