关于前端:记录一些自己用的前端工具函数

import _ from 'lodash';import { toThousands } from '@mx/util/to-thousands';/** * toThousands千分位格式化 * * ### Example * ``` * const n = '12344.33' * toThousands(n); // 12,344.33 * ``` */// 工夫格式化export function getTimeStr (date) {  if (typeof date === 'number') {    date = new Date(date);  }  let hours = `${date.getHours()}`;  let minutes = `${date.getMinutes()}`;  let secodes = `${date.getSeconds()}`;  if (hours.length < 2) {    hours = `0${hours}`;  }  if (minutes.length < 2) {    minutes = `0${minutes}`;  }  if (secodes.length < 2) {    secodes = `0${secodes}`;  }  return `${hours}:${minutes}:${secodes}`;}// 日期格式化export function getDateStr (date, flag = '-') {  if (!date) {    return '';  }  if (typeof date === 'number') {    date = new Date(date);  }  let year = `${date.getFullYear()}`;  let month = `${date.getMonth() + 1}`;  let day = `${date.getDate()}`;  if (month.length < 2) {    month = `0${month}`;  }  if (day.length < 2) {    day = `0${day}`;  }  return `${year}${flag}${month}${flag}${day}`;}// 综合工夫格式化export function formatDate (date) {  if (!date) {    return '--';  }  return `${getDateStr(date)} ${getTimeStr(date)}`;}// 数字格局保留指定位小数,返回字符串格局export function fixedNumber (num, count = 2) {  if (typeof num !== 'number') {    num = Number(num);  }  return num.toFixed(count);}// 金额 分=>元export function amountCentToYuan (cent) {  if (typeof cent !== 'number' || Number.isNaN(cent)) {    return null;  }  return round(cent / 100, 2);}// 金额 元=>分export function amountYuanToCent (yuan) {  if (typeof yuan !== 'number' || Number.isNaN(yuan)) {    return null;  }  return round(yuan * 100, 2);}// 小数四舍五入export function round (number, precision) {  return Math.round(+number + 'e' + precision) / Math.pow(10, precision);}// 千分位格式化，可抉择金额单位为分export function amountToThousands (amount, isCent = false) {  if (!amount && amount !== 0) {    return '';  }  if (isCent) {    amount = Number.parseFloat(amount) / 100;  }  // 产品要强制带小数点两位  let amountStr = toThousands(`${amount}`);  if (!amountStr.includes('.')) {    amountStr += '.00';  } else {    // 小数点后只有一位的话，还须要补齐    if (amountStr.split('.')[1].length < 2) {      amountStr += '0';    }  }  return amountStr;}// 数字大写格局映射export function getNumberCap (num) {  num = num.trim();  if (!num) {    return '';  }  if (!/^(0|[1-9]\d*)(\.\d+)?$/.test(num)) {    return '异样金额';  }  let unit = '千百拾亿千百拾万千百拾元角分';  let str = '';  num += '00';  const p = num.indexOf('.');  if (p >= 0) {    num = num.substring(0, p) + num.substr(p + 1, 2);  }  unit = unit.substr(unit.length - num.length);  for (let i = 0; i < num.length; i++) {    str += '零壹贰叁肆伍陆柒捌玖'.charAt(num.charAt(i)) + unit.charAt(i);  }  return str.replace(/零(千|百|拾|角)/g, '零')    .replace(/(零)+/g, '零')    .replace(/零(万|亿|元)/g, '$1')    .replace(/(亿)万|壹(拾)/g, '$1$2')    .replace(/^元零?|零分/g, '')    .replace(/元$/g, '元整');}// 依据正则剔除字符串指定内容，默认剔除非数字export function replaceByRex (val, rex = /^[0-9]*$/) {  if (!val) {    return '';  }  return Array.from(val).filter(str => Array.isArray(str.match(rex))).join('');}// 剔除字符串中非数字局部并返回export function replaceNotNum (val) {  return replaceByRex(val, /^[0-9]*$/);}// 提出字符串中非数字和字母的局部并返回export function replaceNotNumAndLetter (val) {  return replaceByRex(val, /^[0-9a-zA-Z]*$/);}// 函数节流，多用于提交接口，默认2sexport function throttle (fn, wait = 2000) {  return _.throttle(fn, wait);}// 对象深拷贝export function deepCopy (obj) {  return JSON.parse(JSON.stringify(obj));}// 截取字符串中的数字局部并返回，返回值是字符串格局// 卡号等不太实用，十分大的数字计算会有问题export function getNumberByString (str, isFloat = false, precision = 2) {  str = str.trim();  if (!str) {    return '';  }  const reg = isFloat ? /[0-9.]*/g : /[0-9]*/g;  const resultArr = str.match(reg);  let resultStr = '';  if (Array.isArray(resultArr)) {    resultStr = resultArr.join('');  }  if (!isFloat) {    // 为了保险起见，先转成数字再转回来    return `${Number.parseInt(resultStr)}`;  } else {    // 小数可能存在多个小数点存在，小数点也可能在结尾或者结尾，都须要解决    // 结尾的小数点暂不解决，因为输出小数输一半是必然会通过这一过程的    if (resultStr.startsWith('.')) {      // 结尾的小数点会解决成0.      resultStr = '0' + resultStr;    }    if (resultStr.indexOf('.') !== resultStr.lastIndexOf('.')) {      // 如果有多个小数点，则第二个小数点及之后的内容将会被舍弃      const arr = resultStr.split('.');      resultStr = `${arr[0]}.${arr[1]}`;    }    // 小数位数限度    if (typeof precision === 'number' && precision >= 0) {      if (resultStr.includes('.')) {        let [int, float] = resultStr.split('.');        if (float.length > precision) {          float = float.substring(0, precision);        }        resultStr = `${int}.${float}`;      }    }    // 保险起见，先转成数字再转回来    // 不过只有有小数点，就可能不实用    if (resultStr.includes('.')) {      return resultStr;    }    return `${Number.parseFloat(resultStr)}`;  }}// 银行卡号展现，开始三位有一个空格，之后每四位会有一空格export function showBankNo (bankCardNo) {  if (!bankCardNo) {    return '';  }  let showCardNo = '';  for (let i = 1; i <= bankCardNo.length; i++) {    showCardNo += bankCardNo[i - 1];    if (i === 3) {      showCardNo += ' ';    } else if (i > 4) {      if ((i % 4) === 0 && i !== bankCardNo.length) {        showCardNo += ' ';      }    }  }  return showCardNo;}function compareNumbers (a, b) {  a = Number(a);  b = Number(b);  return a === b ? 0    : a > b ? 1      : -1;}export function formatCommaSeparatedNumbersToNumberArray (v = '') {  if (v === null) { return []; }  let values = v.split(',')    .map(value => { const num = Number(value); if (num) { return num; } })    .filter(v => typeof v === 'number')    .filter(value => {      const v = Number(value);      return v > 0 && Number.isInteger(v);    });  if (values.length === 0) { return []; }  return Array.from(new Set(values)).sort(compareNumbers);}export function formatCommaSeparatedNumbersToArray (v = '') {  if (v === null) { return []; }  let values = v.split(',').filter((value = '') => {    if (value === '') { return false; }    const v = Number(value);    return v > 0 && Number.isInteger(v);  });  if (values.length === 0) { return []; }  return Array.from(new Set(values)).sort(compareNumbers);}// 以后环境辨别export function getEnvRuntime () {  if (/\.dev\.sankuai\.com/.test(location.host)) {    return 'dev';  } else if (/\.test\.sankuai\.com/.test(location.host)) {    return 'test';  } else if (/\.st\.(sankuai|meituan)\.com/.test(location.host)) {    return 'st';  } else if (/(promomis-promotion|promo)\.(sankuai|meituan)\.com/.test(location.host)) {    return 'prod';  } else {    return 'local';  }}// 获取协定模板export function getAgreementTemplate (no, params) {  let agreementTemplate = '';  if (no) {    agreementTemplate = require(`client/business/agreements/${no}.html`);  }  if (agreementTemplate) {    // 协定里存在变量，须要别离填充，具体运算规定不在公共办法中解决，而是由内部传入数据决定    const variable = _.template(agreementTemplate);    return params ? variable(params) : variable();  }  console.warn(`协定${no}不存在`);  return '没有对应协定';}// 递归合并对象,只合并同级字段export function meargeObject (base, opt, copyBase = true) {  if (!base || typeof base !== 'object') {    return opt || {};  }  if (copyBase) {    base = deepCopy(base);  }  if (!opt || typeof opt !== 'object') {    return base;  }  // 递归遍历比照，须要依据typeof来判断  for (const [optKey, optVal] of Object.entries(opt)) {    let val = null;    for (const [baseKey, baseVal] of Object.entries(base)) {      if (baseKey === optKey) {        if (Array.isArray(baseVal)) {          val = baseVal.concat(optVal);        } else if (Array.isArray(optVal)) {          // 这种很奇怪了，原数据不是数组，但新数据是，我就先依照齐全替换解决了          val = optVal;        } else if (typeof baseVal === typeof optVal === 'object') {          val = meargeObject(baseVal, optVal, false);        } else {          val = optVal;        }      }    }    if (!val) {      base[optKey] = optVal;    } else {      base[optKey] = val;    }  }  return base;}// JS下载指定url文件export function downFile (url) {  const iframe = document.createElement('iframe');  iframe.src = url;  iframe.style.display = 'none';  document.body.appendChild(iframe);}