JSON - 蓝桥云课

一.代码部分

<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <title></title>
  </head>

  <body>
    <script>
      var student = {
        name: "zhangsan",
        age: 18,
        gender: "male"
      };
      for (var key in student) {
        console.log(key);
        console.log(student[key]);
      }
    </script>
  </body>
</html>
copy

内置对象的使用写一个函数，格式化日期对象，

<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <title></title>
  </head>

  <body>
    <script>
      function formatDate(d) {
        // 如果 d 不是日期对象的实例，返回空
        if (!d instanceof Date) {
          return;
        }
        var year = d.getFullYear(),
          month = d.getMonth() + 1,
          date = d.getDate(),
          hour = d.getHours(),
          minute = d.getMinutes(),
          second = d.getSeconds();
        month = month < 10 ? "0" + month : month;
        date = date < 10 ? "0" + date : date;
        hour = hour < 10 ? "0" + hour : hour;
        minute = minute < 10 ? "0" + minute : minute;
        second = second < 10 ? "0" + second : second;
        return (
          year +
          "/" +
          month +
          "/" +
          date +
          " " +
          hour +
          ":" +
          minute +
          ":" +
          second
        );
      }
      console.log(formatDate(new Date()));
    </script>
  </body>
</html>
copy

写一个函数去掉数组中的重复元素。

<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <title></title>
  </head>

  <body>
    <script type="text/javascript">
      var array = ["x", "c", "a", "b", "c", "b", "c"];

      function clearArray() {
        var o = {};
        for (var i = 0; i < array.length; i++) {
          var item = array[i];
          if (o[item]) {
            o[item]++;
          } else {
            o[item] = 1;
          }
        }
        var tmpArray = [];
        for (var key in o) {
          if (o[key] == 1) {
            tmpArray.push(key);
          } else {
            if (tmpArray.indexOf(key) == -1) {
              tmpArray.push(key);
            }
          }
        }
        return tmpArray;
      }

      console.log(clearArray(array));
    </script>
  </body>
</html>
copy

写一个函数判断一个字符串中出现次数最多的字符，并统计这个字符出现的次数。

<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <title></title>
  </head>
  <body>
    <script type="text/javascript">
      var str = "daskljahiagnaknscsjdwfanalvnahdpwod";

      function max() {
        var o = {};
        for (var i = 0; i < str.length; i++) {
          var item = str.charAt(i);
          if (o[item]) {
            o[item]++;
          } else {
            o[item] = 1;
          }
        }
        var max = 0;
        for (var key in o) {
          if (max < o[key]) {
            max = o[key];
            var tmp;
            tmp = key;
          }
        }
        console.log("出现次数最多的字符是:" + tmp + "出现次数为：" + max);
      }

      max(str);
    </script>
  </body>
</html>
copy

二.学习笔记

“Web开发基础”实验报告