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常用的JavaScript代码技巧 (一)字符串、数字

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前言:

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作为一名前端程序员需要了解一些常用的JavaScript代码技巧,这样可以提高代码效率,我们就来看看具体的内容吧。

字符串类

1.比较时间

const time1 = "2022-03-05 10:00:00";const time2 = "2022-03-05 10:00:01";const overtime = time1 < time2;// overtime => true

2.货币格式

const ThousandNum = num => num.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ",");const cash = ThousandNum(100000000);// cash => 100,000,000

3.随机密码

const Randompass = len => Math.random().toString(36).substr(3, len);const pass = RandomId(8);// pass => "7nf6tgru"

4.随机HEX颜色值

const RandomColor = () => "#" + Math.floor(Math.random() * 0xffffff).toString(16).padEnd(6, "0");const color = RandomColor();// color => "##26330b"

5.评价星星

const StartScore = rate => "★★★★★☆☆☆☆☆".slice(5 - rate, 10 - rate);const start = StartScore(4);// start => ★★★★☆

6.获得URL参数

const url = new URL(';);const params = new URLSearchParams(url.search.replace(/\?/ig, ""));params.has('sex'); // trueparams.get("sex"); // "male"

数字类数字处理,替代Math.floor() 和 Math.ceil()

const n1 = ~~ 1.19;const n2 = 2.29 | 0;const n3 = 3.39 >> 0;// n1 n2 n3 => 1 2 3

2.补零

const FillZero = (num, len) => num.toString().padStart(len, "0");const num = FillZero(123, 5);// num => "00123"

3.转换成数值

const num1 = +null;const num2 = +"";const num3 = +false;const num4 = +"59";// num1 num2 num3 num4 => 0 0 0 59

4.时间戳

const timestamp = +new Date("2022-03-07");// timestamp => 1646611200000

5.小数

const RoundNum = (num, decimal) => Math.round(num * 10 ** decimal) / 10 ** decimal;const num = RoundNum(1.2345, 2);// num => 1.23

6.奇偶校验

const YEven = num => !!(num & 1) ? "no" : "yes";const num = YEven(1);// num => "no"const num = YEven(2);// num => "yes"

7.获得最小值最大值

const arr = [0, 1, 2, 3];const min = Math.min(...arr);const max = Math.max(...arr);// min max => 0 3

8.生成范围随机数

const RandomNum = (min, max) => Math.floor(Math.random() * (max - min + 1)) + min;const num = RandomNum(1, 10); // 6 每次运行可能不一样

待续................

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