<!DOCTYPE html>
<html>
<body>
<h2>JavaScript 数值</h2>
<p>写数值时用不用小数点均可：</p>
<p id="demo"></p>
<script>
var x1 = 34.00;
var x2 = 34;
var x3 = 3.14;
document.getElementById("demo").innerHTML =
x1 + "<br>" + x2 + "<br>" + x3;
</script>
</body>
</html>