JavaScript typeof运算符-在线运行代码案例-大卫编程网

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<title>JavaScript typeof运算符示例 - 基础教程(div.cn)</title>
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<body>
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<h1> JavaScript typeof运算符</h1>
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<p> typeof运算符返回变量或表达式的类型：</p>
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<script>
document.write(
  typeof "" + "<br>" +
  typeof "Json" + "<br>" +
  typeof "42" + "<br>" +
  typeof 42 + "<br>" +
  typeof true + "<br>" +
  typeof false + "<br>" +
  typeof undefined + "<br>" +
  typeof null + "<br>" +
  typeof {name:"Json", age:22} + "<br>" +
  typeof [2, 4, 6, 8] + "<br>" +
  typeof function myFunc(){}
);
</script>
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<p> <b>注意：</b> <b> typeof </b>运算符为数组返回"object"，因为在JavaScript数组中是对象。</p>
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</body>
</html>