<!DOCTYPE html>
<html>
<body>
<p>切勿将字符串创建为对象。</p>
<p>字符串和对象无法安全地进行比较。</p>
<p id="demo"></p>
<script>
var x = "Bill"; // x 是字符串
var y = new String("Bill"); // y 是对象
document.getElementById("demo").innerHTML = x===y;
</script>
</body>
</html>