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JavaScript

Posted by msdsmd sm,dfsadf
msdsmd sm,dfsadf
1,124 Points

Please someone explain this very short line of code

<!DOCTYPE html>
<html>
<head>
<style>

</style>
</head>
<body>


<button onclick="myFunction()">Try it</button>



<script>  let s = false;
function myFunction() {
s = !s
alert(s)

}
</script>

</body>
</html>

Why I do I get the message false when I clicked button twice

1 Answer

Michael Kobela
.a{fill-rule:evenodd;}techdegree seal-36
Michael Kobela
Full Stack JavaScript Techdegree Graduate 19,570 Points

The ! is the javascript logical NOT operator: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Logical_NOT

Each time you click the buttons, s is changed to its opposite.

false == !true; true == !false;