Conditional checkbox [closed]

1. How to write if condition for checkbox in Javascript?
2. Can a checkbox be checked and disabled?

How to write if condition for checkbox in Javascript?

getElementById('takenBefore'). addEventListener('click', event => if(event. target. checked) alert("Checkbox checked!"); );

Can a checkbox be checked and disabled?

In checkboxes, for example, you can check them on or off (thus setting the CHECKED state) but you don't change the value of the field.