处理获取当前日期---------------年月日//时分秒

当前时间，先分组匹配，以数组下标索引匹配定义的汉字进行替换

处理日期方法

/* 日期格式化 */
const formatTime = function formatTime(time, template) {if (typeof time !== "string") {time = new Date().toLocaleString('zh-CN', { hour12: false });}if (typeof template !== "string") {template = "{0}年{1}月{2}日 {3}:{4}:{5}";}let arr = [];if (/^\d{8}$/.test(time)) {let [, $1, $2, $3] = /^(\d{4})(\d{2})(\d{2})$/.exec(time);arr.push($1, $2, $3);} else {arr = time.match(/\d+/g);}return template.replace(/\{(\d+)\}/g, (_, $1) => {let item = arr[$1] || "00";if (item.length < 2) item = "0" + item;return item;

导入定义的工具方法

import _ from '../assets/utils'

import React, { useMemo, useEffect } from 'react'
import timg from '../assets/images/timg.jpg'
import './HomeHead.less'
import { connect } from 'react-redux'
import action from '../store/action'
import { useNavigate } from 'react-router-dom'const HomeHead = function HomeHead(props) {const navigate = useNavigate()/* 计算时间中的月和日 */let { today, info, queryUserInfoAsync } = propslet time = useMemo(() => {//通过正则取数字let [, year, month, day] = today.match(/^\d{0}(\d{4})(\d{2})(\d{2})$/),area = ['零','一', '二', '三', '四','五','六','七','八','九','十','十一','十二',]return {year: +year + '年',month: area[+month] + '月',day: +day + '日',}}, [today])// 第一次渲染完:如果info中没有信息,我们尝试派发一次,获取到登陆者信息useEffect(() => {if (!info) {queryUserInfoAsync()}}, [])return (<header className="home-head-box">{/* 时间，标题 */}<div className="info"><div className="time"><span>{time.year}</span><div className="month_day"><span>{time.month}</span><span>{time.day}</span></div></div><h2 className="title">知乎日报</h2></div>{/* {头像} */}<divclassName="picture"onClick={() => {navigate('/personal')}}><img src={info ? info.pic : timg} alt="" /></div></header>)
}
export default connect((state) => state.base, action.base)(HomeHead)

截取获取当前时分秒

new Date().toLocaleString().split('/').join('').slice(-8)
'16:30:09'

截取掉冒号,获取当前时分秒

new Date().toLocaleString().split('/').join('').slice(-8).split(':').join('')//'163037'let time = new Date().toLocaleString().split('/').join('').slice(-8).split(':').join('')console.log(time.match(/^\d{0}(\d{2})(\d{2})(\d{2})$/));

使用数组解构接收，

 let time = new Date().toLocaleString().split('/').join('').slice(-8).split(':').join('')
let [,hour,minute,second]= time.match(/^\d{0}(\d{2})(\d{2})(\d{2})$/)
console.log(hour,minute,second);

截取掉/ （斜杠）获取当前年月日

new Date().toLocaleString().split('/').join('').slice(0,8)
//'20231212 '

new Date().toLocaleString().split('/').join('').slice(0,8).match(/^\d{0}(\d{4})(\d{2})(\d{2})$/)

使用数组解构接收，

   let time = new Date().toLocaleString().split('/').join('').slice(0,8).match(/^\d{0}(\d{4})(\d{2})(\d{2})$/)let [, year, month, day] = timeconsole.log(year, month, day);//不需要的直接 ， 为空就行