1.复制文本到剪切板

const copyTextToClipboard = (text) => navigator.clipboard.writeText(text);

copyTextToClipboard("Hello World!!!")

2.获取某个日期位于当年的第几天

const dayOfYear = (date) =>
  Math.floor((date - new Date(data.getFullYear(), 0, 0)) / 1000 / 60 / 60 / 24);

dayOfYear(new Date(2024, 11, 11));

3.将rgba颜色灰度化（基于光感加权平均）

const gray = (r, g, b) => 0.2126 * r + 0.7152 * g + 0.0722 * b;

gray(50, 100, 150);

4.解析url中的参数

const parseQueryParams = (url) => {
  let q = {};
  url.replace(/([^?&=]+)=([^&]+)/g, (_, k, v) => (q[k] = v));
  return q;
};

parseQueryParams('http://www.test.com?a=1&b=2');

parseQueryParams('a=1&b=2');

###5.筛选对象属性

const pick = (obj, ...props) =>
  Object.fromEntries(Object.entries(obj).filter(([k]) => props.includes(k)));

pick({a: 1, b: 2, c: 3}, 'a', 'b');

6.随机HEX颜色

const randomColor = () =>
  '#' +
  Math.floor(Math.random() * 0xffffff)
    .toString(16)
    .padEnd(6, '0');

randomColor();

7.生成随机字符串

const randomString = () => Math.random().toString(36).slice(2);

randomString();

8.去掉字符串中的元素标记

const removeStringTag = (code_fragment) =>
  new DOMParser().parseFromString(code_fragment, 'text/html').body
    .textContent || '';

removeStringTag(`<div>Hello World!!</div>`)