131 lines
4.4 KiB
HTML
131 lines
4.4 KiB
HTML
<!DOCTYPE html>
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<html lang="en">
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<head>
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<meta charset="UTF-8">
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<meta name="viewport" content="width=device-width, initial-scale=1.0">
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<title>Document</title>
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</head>
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<body>
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<script>
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// 1、字符串操作
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// let str1 = "1203def456";
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// let num1 = parseInt(str1);
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// console.log("num1的值为:", num1);
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// console.log("num1的数据类型:", typeof num1);
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// let str2 = num1.toString();
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// console.log("str2的值为:", str2);
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// console.log("str2中的字符'0':", str2.charAt(1));
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// 2、矩形面积计算函数
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// function calculateArea(width, height) {
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// let area = width * height;
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// return area;
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// }
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// let scaleFactor = 2;
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// let width = 5;
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// let height = 3;
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// let area = calculateArea(width * scaleFactor, height * scaleFactor);
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// console.log("计算后的面积为:", area);
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// 3、 使用for循环计算1+2+3+4+5的和
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// let sum = 0;
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// for (let i = 1; i <= 5; i++) {
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// sum += i;
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// }
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// console.log("1+2+3+4+5的和为:", sum);
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// 4. 通过提示框输入整数并判断奇偶
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// let inputNum = prompt("请输入一个整数:");
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// let result = (inputNum % 2 === 0) ? "该数是偶数" : "该数是奇数";
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// alert(result);
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// 5、操作数组
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// 5.1 向arr1添加元素后
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// 5.2 删除arr2最后一个元素后
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// 5.3 删除arr3第一个元素后
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// 5.4 在arr4开头添加元素后
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// 5.5 数组转字符串
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// 5.5 字符串转数组
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// 5.6 拼接后的数组
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// let arr1 = [1, 2, 3];
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// let newLength1 = arr1.push(4);
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// console.log("5.1 向arr1添加元素后:", arr1, "新长度:", newLength1);
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// let arr2 = ['apple', 'banana', 'orange'];
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// let removedElement2 = arr2.pop();
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// console.log("5.2 删除arr2最后一个元素后:", arr2, "被删除的元素:", removedElement2);
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// let arr3 = [1, 2, 3];
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// let removedElement3 = arr3.shift();
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// console.log("5.3 删除arr3第一个元素后:", arr3, "被删除的元素:", removedElement3);
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// let arr4 = [1, 2, 3];
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// let newLength4 = arr4.unshift(0);
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// console.log("5.4 在arr4开头添加元素后:", arr4, "新长度:", newLength4);
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// let arr5 = [1, 2, 3, 4];
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// let strFromArr = arr5.join('-');
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// let arrFromStr = strFromArr.split('-');
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// console.log("5.5 数组转字符串:", strFromArr);
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// console.log("5.5 字符串转数组:", arrFromStr);
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// let arr6 = ['A', 'B', "C"];
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// let arr7 = [true, false];
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// let concatenatedArr = arr6.concat(arr7);
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// console.log("5.6 拼接后的数组:", concatenatedArr);
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// 6. 使用for循环循环打印fruits数组的元素
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// let fruits = ["apple", "banana", "cherry"];
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// console.log("6. fruits数组元素:");
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// for (let i = 0; i < fruits.length; i++) {
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// console.log(fruits[i]);
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// }
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// 7. 使用for...in循环遍历对象的属性
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// let person = {
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// name: "John",
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// age: 30,
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// city: "New York"
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// };
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// console.log("7. 遍历person对象:");
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// for (let key in person) {
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// console.log("属性名:", key, "属性值:", person[key]);
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// }
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// 8. 获得当前日期并格式化
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function getCurrentDateFormatted() {
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let now = new Date();
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// 获取年、月、日、时、分、秒
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let year = now.getFullYear();
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let month = String(now.getMonth() + 1).padStart(2, '0');
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let day = String(now.getDate()).padStart(2, '0');
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let hours = String(now.getHours()).padStart(2, '0');
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let minutes = String(now.getMinutes()).padStart(2, '0');
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let seconds = String(now.getSeconds()).padStart(2, '0');
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// 格式化日期字符串
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let formattedDate = `${year}年${month}月${day}日 ${hours}:${minutes}:${seconds}`;
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return formattedDate;
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}
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// 在控制台输出
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let currentDate = getCurrentDateFormatted();
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console.log("8. 当前日期:", currentDate);
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// 在页面上显示
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document.body.innerHTML += `<p>当前时间: ${currentDate}</p>`;
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</script>
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</body>
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</html> |