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来源：3-9 Map的应用

清夏_

2022-09-26 15:24:11

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8" />
    <title></title>
  </head>
  <body>
    <p>我是一号p标签</p>
    <p>我是二号p标签</p>
    <p>我是三号p标签</p>

    <script type="text/javascript">
      const [p1, p2, p3] = document.querySelectorAll("p"); //Nodelist
      // console.log(p1, p2, p3);

      const m = new Map([
        [p1, "red"],
        [p2, "green"],
        [p3, "blue"],
      ]);

      m.forEach((color, elem) => {
        elem.style.color = color;
      });

      console.log(m);
    </script>
  </body>
</html>

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      // console.log(
      //   new Map([
      //     ["name", "YangLiJun"],
      //     ["age", 18],
      //     ["sex", "male"],
      //   ])
      // ); //Map(3) {'name' => 'YangLiJun', 'age' => 18, 'sex' => 'male'}

      console.log(
        new Map([
          [name, "YangLiJun"],
          ["age", 18],
          ["sex", "male"],
        ])
      ); //Map(3) {'' => 'YangLiJun', 'age' => 18, 'sex' => 'male'}
    </script>
  </body>
</html>