代码示例:(标识:js_oper_unary_minus)
<!DOCTYPE html>
<html>
<body>

<h1>JavaScript 运算符</h1>

<h2>一元减号</h2>

<p id="demo"></p>

<script>
let x = 5;
document.getElementById("demo").innerHTML = -x;
</script>

</body>
</html>
运行结果: