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JavaScript AJAX Basics (retiring) AJAX and APIs Adding jQuery

Posted by Eric Ridolfi
Eric Ridolfi
19,417 Points

$('button') on removeClass but not $(this)?

Maybe I missed it but why is $('button').removeClass('selected') used instead of $(this).removeClass('selected')?

$(document).ready(function () {
    $('button').click(function () {
        $('button').removeClass("selected");
        $(this).addClass("selected");
    }); // end button.click
}); // end ready

1 Answer

Paolo Scamardella
Paolo Scamardella
24,828 Points
Paolo Scamardella
Paolo Scamardella
24,828 Points

Because, in this case, if you just use $(this).removeClass("selected") instead of $('button').removeClass("selected"), then all your buttons will be "selected". If you keep clicking on all your buttons, then all buttons will be highlighted. The reason David is using $('button').removeClass("selected") first is because he wants to make sure it will remove all selected class to all buttons (including the one that is being clicked) and then reapply the selected class to only the one that is being clicked. Doing so, the other buttons will not be highlighted while clicking on the current button. Hope that makes sense. If not, I will try to explain it better.

Remember, $('button') means to all buttons on your screen and not just a single button. Using $(this) inside $('button').click refers to the button that is being clicked.

Eric Ridolfi
Eric Ridolfi
19,417 Points

Thank you that does make sense.