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

<h2>JavaScript 函数</h2>

<p>本例调用函数把华氏度转换为摄氏度:</p>

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

<script>
function toCelsius(f) {
    return (5/9) * (f-32);
}
document.getElementById("demo").innerHTML = toCelsius(86);
</script>

</body>
</html>
运行结果: