25 String 对象中的属性
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<head>
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<title>Document</title>
<!-- String 对象中的属性 -->
</head>
<body>
<script>
var str = new String("JavaScript");
String.prototype.name = null;
str.name = "Hello World!";
document.write(str.constructor + "</br>");
// 输出：function String(){[native code]}
document.write(str.length + "</br>");
// 输出：10
document.write(str.name);
// 输出：Hello World!
</script>
</body>
</html>