​x
 
<!DOCTYPE html>
<html>
<body>
​
<h1>JavaScript 数字方法</h1>
​
<p>valueOf() 把数字返回为数字：</p>
​
<p id="demo"></p>
​
<script>
var x = 123;
​
document.getElementById("demo").innerHTML = 
  x.valueOf() + "<br>" +
  (123).valueOf() + "<br>" +
  (100 + 23).valueOf();
</script>
​
</body>
</html>
​