<!DOCTYPE html>
<html>
<body>
<h1>JavaScript 运算符</h1>
<h2>! 运算符</h2>
<p id="demo1"></p>
<p id="demo2"></p>
<script>
document.getElementById("demo1").innerHTML = (5 == 8);
document.getElementById("demo2").innerHTML = !(5 == 8);
</script>
</body>
</html>