38个实用的JavaScript技巧
今天这篇文章，我想跟大家分享一些我在日常工作中收集整理的有用JavaScript技巧，希望这些技巧能够帮助你提升开发效率。
01、重新加载当前页面
const reload = () => location.reload();
reload();
02、滚动到页面顶部
const goToTop = () => window.scrollTo(0, 0);
goToTop();
03、元素滚动
将元素平滑地滚动到视口起点：
const scrollToTop = (element) => element.scrollIntoView({ behavior: "smooth", block: "start" });
scrollToTop(document.body);
将元素平滑地滚动到视口端点：
const scrollToBottom = (element) => element.scrollIntoView({ behavior: "smooth", block: "end" });
scrollToBottom(document.body);
04、检查当前浏览器是否为Internet Explorer
const isIE = !!document.documentMode;
05、从给定文本中去除HTML
const stripHtml = (html) => new DOMParser().parseFromString(html, 'text/html').body.textContent || '';
stripHtml('<div>test</div>'); // 'test'
06、重定向
const goTo = (url) => (location.href = url);
07、复制文本到剪贴板
const copy = (text) => navigator.clipboard?.writeText && navigator.clipboard.writeText(text);
copy('你需要粘贴的文本');
08、异步函数检查
const isAsyncFunction = (v) => Object.prototype.toString.call(v) === '[object AsyncFunction]';
isAsyncFunction(async function () {}); // true
09、截断数字
const toFixed = (n, fixed) => `${n}`.match(new RegExp(`^-?\\d+(?:.\\d{0,${fixed}})?`))[0];
toFixed(10.255, 2); // 10.25
10、四舍五入到最接近的数字
const round = (n, decimals = 0) => Number(`${Math.round(`${n}e${decimals}`)}e-${decimals}`);
round(10.255, 2); // 10.26
11、零填充
const replenishZero = (num, len, zero = 0) => num.toString().padStart(len, zero);
replenishZero(8, 2); // 08
12、删除无效属性
const removeNullUndefined = (obj) => Object.entries(obj).reduce((a, [k, v]) => (v == null ? a : ((a[k] = v), a)), {});
removeNullUndefined({name: '', age: undefined, sex: null}); // { name: '' }
13、反转对象键值对
const invert = (obj) => Object.keys(obj).reduce((res, k) => Object.assign(res, { [obj[k]]: k }), {});
invert({name: 'jack'}); // {jack: 'name'}
14、将字符串转换为对象
const strParse = (str) => JSON.parse(str.replace(/(\w+)\s*:/g, (_, p1) => `"${p1}":`).replace(/'/g, '"'));
strParse('{name: "jack"}');
日期处理技巧
15、检查日期是否为今天
const isToday = (date) => date.toISOString().slice(0, 10) === new Date().toISOString().slice(0, 10);
16、日期转换
const formatYmd = (date) => date.toISOString().slice(0, 10);
formatYmd(new Date());
17、秒转换为 hh:mm:ss 格式
const formatSeconds = (s) => new Date(s * 1000).toISOString().substr(11, 8);
formatSeconds(200); // 00:03:20
18、获取某年某月的第一天
const getFirstDate = (d = new Date()) => new Date(d.getFullYear(), d.getMonth(), 1);
getFirstDate(new Date('2024/05'));
19、获取某年某月的最后一天
const getLastDate = (d = new Date()) => new Date(d.getFullYear(), d.getMonth() + 1, 0);
getLastDate(new Date('2023/03/04'));
20、获取给定年份的特定月份的总天数
const getDaysNum = (year, month) => new Date(year, month, 0).getDate;
const day = getDaysNum(2024, 2); // 29
数组处理技巧
21、生成数组
const createArr = (n) => Array.from(new Array(n), (v, i) => i);
createArr(100);
22、随机排列数组
const randomSort = (list) => list.sort(() => Math.random() - 0.5);
randomSort([0,1,2,3,4,5,6,7,8,9]); // 随机排列结果
23、数组去重
const removeDuplicates = (list) => [...new Set(list)];
removeDuplicates([0, 0, 2, 4, 5]); // [0,2,4,5]
24、根据唯一值去重
const duplicateById = (list) => [...list.reduce((prev, cur) => prev.set(cur.id, cur), new Map()).values()];
duplicateById([{id: 1, name: 'jack'}, {id: 2, name: 'rose'}, {id: 1, name: 'jack'}]);
25、多个数组的交集
const intersection = (a, ...arr) => [...new Set(a)].filter((v) => arr.every((b) => b.includes(v)));
intersection([1, 2, 3, 4], [2, 3, 4, 7, 8], [1, 3, 4, 9]); // [3, 4]
26、查找数组中最大值的索引
const indexOfMax = (arr) => arr.reduce((prev, curr, i, a) => (curr > a[prev] ? i : prev), 0);
indexOfMax([1, 3, 9, 7, 5]); // 2
27、查找最小值索引
const indexOfMin = (arr) => arr.reduce((prev, curr, i, a) => (curr < a[prev] ? i : prev), 0);
indexOfMin([2, 5, 3, 4, 1, 0, 9]); // 5
28、查找最接近的数值
const closest = (arr, n) => arr.reduce((prev, curr) => (Math.abs(curr - n) < Math.abs(prev - n) ? curr : prev));
closest([29, 87, 8, 78, 97, 20, 75, 33, 24, 17], 50); // 33
29、压缩多个数组
const zip = (...arr) => Array.from({ length: Math.max(...arr.map((a) => a.length)) }, (_, i) => arr.map((a) => a[i]));
zip([1,2,3,4], ['a', 'b', 'c', 'd'], ['A', 'B', 'C', 'D']);
30、矩阵行列交换
const transpose = (matrix) => matrix[0].map((col, i) => matrix.map((row) => row[i]));
transpose([[1, 2, 3], [4, 5, 6], [7, 8, 9]]);
数字转换
31、基数转换
const toDecimal = (num, n = 10) => num.toString(n);
toDecimal(10, 2); // '1010'
const toDecimalism = (num, n = 10) => parseInt(num, n);
toDecimalism(1010, 2); // 10
其他技巧
32、比较两个对象
const isEqual = (...objects) => objects.every(obj => JSON.stringify(obj) === JSON.stringify(objects[0]));
isEqual({name: 'jack'}, {name: 'jack'}); // true
33、随机颜色生成
const getRandomColor = () => `#${Math.floor(Math.random() * 0
xffffff).toString(16)}`;
getRandomColor(); // '#4c2fd7'
34、颜色格式转换
const hexToRgb = (hex) => hex.replace(/^#?([a-f\d])([a-f\d])([a-f\d])$/i, (_, r, g, b) => `#${r}${r}${g}${g}${b}${b}`).substring(1).match(/.{2}/g).map((x) => parseInt(x, 16));
hexToRgb('#00ffff'); // [0, 255, 255]
35、生成随机IP地址
const randomIp = () => Array(4).fill(0).map((_, i) => Math.floor(Math.random() * 255) + (i === 0 ? 1 : 0)).join('.');
36、生成UUID
const uuid = (a) => (a ? (a ^ ((Math.random() * 16) >> (a / 4))).toString(16) : ([1e7] + -1e3 + -4e3 + -8e3 + -1e11).replace(/[018]/g, uuid));
uuid();
37、获取Cookie
const getCookie = () => document.cookie.split(';').map((item) => item.split('=')).reduce((acc, [k, v]) => (acc[k.trim().replace('"', '')] = v) && acc, {});
getCookie();
38、强制等待
const sleep = async (t) => new Promise((resolve) => setTimeout(resolve, t));
sleep(2000).then(() => { console.log('time') });
总结
以上就是我今天跟你分享的38个实用的JavaScript技巧，记得收藏以备不时之需。感谢阅读，祝开发愉快！