常用工具函数
日常开发中,面对各种不同的需求,我们经常会用到以前开发过的一些工具函数,把这些工具函数收集起来,将大大提高我们的开发效率。
1、校验数据类型
export const typeOf = function(obj) { return Object.prototype.toString.call(obj).slice(8, -1).toLowerCase() }
示例:
typeOf('逍遥星辰') // string typeOf([]) // array typeOf(new Date()) // date typeOf(null) // null typeOf(true) // boolean typeOf(() => { }) // function
2、防抖
export const debounce = (() => { let timer = null return (callback, wait = 800) => { timer&&clearTimeout(timer) timer = setTimeout(callback, wait) } })()
示例:
如 vue 中使用
methods: { loadList() { debounce(() => { console.log('加载数据') }, 500) } }
3、节流
export const throttle = (() => { let last = 0 return (callback, wait = 800) => { let now = +new Date() if (now - last > wait) { callback() last = now } } })()
4、手机号脱敏
export const hideMobile = (mobile) => { return mobile.replace(/^(\d{3})\d{4}(\d{4})$/, "$1****$2") }
5、开启全屏
export const launchFullscreen = (element) => { if (element.requestFullscreen) { element.requestFullscreen() } else if (element.mozRequestFullScreen) { element.mozRequestFullScreen() } else if (element.msRequestFullscreen) { element.msRequestFullscreen() } else if (element.webkitRequestFullscreen) { element.webkitRequestFullScreen() } }
6、关闭全屏
export const exitFullscreen = () => { if (document.exitFullscreen) { document.exitFullscreen() } else if (document.msExitFullscreen) { document.msExitFullscreen() } else if (document.mozCancelFullScreen) { document.mozCancelFullScreen() } else if (document.webkitExitFullscreen) { document.webkitExitFullscreen() } }
7、大小写转换
参数:
- str 待转换的字符串
- type 1-全大写 2-全小写 3-首字母大写
export const turnCase = (str, type) => { switch (type) { case 1: return str.toUpperCase() case 2: return str.toLowerCase() case 3: //return str[0].toUpperCase() + str.substr(1).toLowerCase() // substr 已不推荐使用 return str[0].toUpperCase() + str.substring(1).toLowerCase() default: return str } }
示例:
turnCase('vue', 1) // VUE turnCase('REACT', 2) // react turnCase('vue', 3) // Vue
8、解析URL参数
export const getSearchParams = () => { const searchPar = new URLSearchParams(window.location.search) const paramsObj = {} for (const [key, value] of searchPar.entries()) { paramsObj[key] = value } return paramsObj }
示例:
// 假设目前位于 https://****com/index?id=154513&age=18; getSearchParams(); // {id: "154513", age: "18"}
9、判断手机是Andoird还是IOS
/** * 1: ios * 2: android * 3: 其它 */ export const getOSType=() => { let u = navigator.userAgent, app = navigator.appVersion; let isAndroid = u.indexOf('Android') > -1 || u.indexOf('Linux') > -1; let isIOS = !!u.match(/\(i[^;]+;( U;)? CPU.+Mac OS X/); if (isIOS) { return 1; } if (isAndroid) { return 2; } return 3; }
10、数组对象根据字段去重
参数:
- arr 要去重的数组
- key 根据去重的字段名
export const uniqueArrayObject = (arr = [], key = 'id') => { if (arr.length === 0) return let list = [] const map = {} arr.forEach((item) => { if (!map[item[key]]) { map[item[key]] = item } }) list = Object.values(map) return list }
示例:
const responseList = [ { id: 1, name: '逍遥星辰' }, { id: 2, name: '黄老爷' }, { id: 3, name: '张麻子' }, { id: 1, name: '黄老爷' }, { id: 2, name: '张麻子' }, { id: 3, name: '逍遥星辰' }, { id: 1, name: '逍遥星辰' }, { id: 2, name: '黄老爷' }, { id: 3, name: '张麻子' }, ] uniqueArrayObject(responseList, 'id') // [{ id: 1, name: '逍遥星辰' },{ id: 2, name: '黄老爷' },{ id: 3, name: '张麻子' }]
11、滚动到页面顶部
export const scrollToTop = () => { const height = document.documentElement.scrollTop || document.body.scrollTop; if (height > 0) { window.requestAnimationFrame(scrollToTop); window.scrollTo(0, height - height / 8); } }
12、滚动到元素位置
export const smoothScroll = element =>{ document.querySelector(element).scrollIntoView({ behavior: 'smooth' }); };
示例:
smoothScroll('#target'); // 平滑滚动到 ID 为 target 的元素
13、uuid
export const uuid = () => { const temp_url = URL.createObjectURL(new Blob()) const uuid = temp_url.toString() URL.revokeObjectURL(temp_url) //释放这个url return uuid.substring(uuid.lastIndexOf('/') + 1) }
示例:
uuid() // a640be34-689f-4b98-be77-e3972f9bffdd
不过要吐槽一句的是,uuid一般应由后端来进行生成
14、金额格式化
参数:
- {number} number:要格式化的数字
- {number} decimals:保留几位小数
- {string} dec_point:小数点符号
- {string} thousands_sep:千分位符号
export const moneyFormat = (number, decimals, dec_point, thousands_sep) => { number = (number + '').replace(/[^0-9+-Ee.]/g, '') const n = !isFinite(+number) ? 0 : +number const prec = !isFinite(+decimals) ? 2 : Math.abs(decimals) const sep = typeof thousands_sep === 'undefined' ? ',' : thousands_sep const dec = typeof dec_point === 'undefined' ? '.' : dec_point let s = '' const toFixedFix = function(n, prec) { const k = Math.pow(10, prec) return '' + Math.ceil(n * k) / k } s = (prec ? toFixedFix(n, prec) : '' + Math.round(n)).split('.') const re = /(-?\d+)(\d{3})/ while (re.test(s[0])) { s[0] = s[0].replace(re, '$1' + sep + '$2') } if ((s[1] || '').length < prec) { s[1] = s[1] || '' s[1] += new Array(prec - s[1].length + 1).join('0') } return s.join(dec) }
示例:
moneyFormat(10000000) // 10,000,000.00 moneyFormat(10000000, 3, '.', '-') // 10-000-000.000
15、存储操作
class MyCache { constructor(isLocal = true) { this.storage = isLocal ? localStorage : sessionStorage } setItem(key, value) { if (typeof (value) === 'object') value = JSON.stringify(value) this.storage.setItem(key, value) } getItem(key) { try { return JSON.parse(this.storage.getItem(key)) } catch (err) { return this.storage.getItem(key) } } removeItem(key) { this.storage.removeItem(key) } clear() { this.storage.clear() } key(index) { return this.storage.key(index) } length() { return this.storage.length } } const localCache = new MyCache() const sessionCache = new MyCache(false) export { localCache, sessionCache }
示例:
localCache.getItem('user') sessionCache.setItem('name','树哥') sessionCache.getItem('token') localCache.clear()
16、下载文件
参数:
- api 接口
- params 请求参数
- fileName 文件名
const downloadFile = (api, params, fileName, type = 'get') => { axios({ method: type, url: api, responseType: 'blob', params: params }).then((res) => { let str = res.headers['content-disposition'] if (!res || !str) { return } let suffix = '' // 截取文件名和文件类型 if (str.lastIndexOf('.')) { fileName ? '' : fileName = decodeURI(str.substring(str.indexOf('=') + 1, str.lastIndexOf('.'))) suffix = str.substring(str.lastIndexOf('.'), str.length) } // 如果支持微软的文件下载方式(ie10+浏览器) if (window.navigator.msSaveBlob) { try { const blobObject = new Blob([res.data]); window.navigator.msSaveBlob(blobObject, fileName + suffix); } catch (e) { console.log(e); } } else { // 其他浏览器 let url = window.URL.createObjectURL(res.data) let link = document.createElement('a') link.style.display = 'none' link.href = url link.setAttribute('download', fileName + suffix) document.body.appendChild(link) link.click() document.body.removeChild(link) window.URL.revokeObjectURL(link.href); } }).catch((err) => { console.log(err.message); }) }
示例:
downloadFile('/api/download', {id}, '文件名')
17、时间操作
关于时间操作,没必要自己再写一大串代码了,强烈推荐使用 day.js
Day.js 是一个仅 2kb 大小的轻量级 JavaScript 时间日期处理库,下载、解析和执行的JavaScript更少,为代码留下更多的时间。
18、深拷贝
export const clone = parent => { // 判断类型 const isType = (obj, type) => { if (typeof obj !== "object") return false; const typeString = Object.prototype.toString.call(obj); let flag; switch (type) { case "Array": flag = typeString === "[object Array]"; break; case "Date": flag = typeString === "[object Date]"; break; case "RegExp": flag = typeString === "[object RegExp]"; break; default: flag = false; } return flag; }; // 处理正则 const getRegExp = re => { var flags = ""; if (re.global) flags += "g"; if (re.ignoreCase) flags += "i"; if (re.multiline) flags += "m"; return flags; }; // 维护两个储存循环引用的数组 const parents = []; const children = []; const _clone = parent => { if (parent === null) return null; if (typeof parent !== "object") return parent; let child, proto; if (isType(parent, "Array")) { // 对数组做特殊处理 child = []; } else if (isType(parent, "RegExp")) { // 对正则对象做特殊处理 child = new RegExp(parent.source, getRegExp(parent)); if (parent.lastIndex) child.lastIndex = parent.lastIndex; } else if (isType(parent, "Date")) { // 对Date对象做特殊处理 child = new Date(parent.getTime()); } else { // 处理对象原型 proto = Object.getPrototypeOf(parent); // 利用Object.create切断原型链 child = Object.create(proto); } // 处理循环引用 const index = parents.indexOf(parent); if (index != -1) { // 如果父数组存在本对象,说明之前已经被引用过,直接返回此对象 return children[index]; } parents.push(parent); children.push(child); for (let i in parent) { // 递归 child[i] = _clone(parent[i]); } return child; }; return _clone(parent); };
此方法存在一定局限性:一些特殊情况没有处理: 例如Buffer对象、Promise、Set、Map。
如果确实想要完备的深拷贝,推荐使用 lodash 中的 cloneDeep 方法。
19、模糊搜索
参数:
- list 原数组
- keyWord 查询的关键词
- attribute 数组需要检索属性
export const fuzzyQuery = (list, keyWord, attribute = 'name') => { const reg = new RegExp(keyWord) const arr = [] for (let i = 0; i < list.length; i++) { if (reg.test(list[i][attribute])) { arr.push(list[i]) } } return arr }
示例:
const list = [ { id: 1, name: '树哥' }, { id: 2, name: '黄老爷' }, { id: 3, name: '张麻子' }, { id: 4, name: '汤师爷' }, { id: 5, name: '胡万' }, { id: 6, name: '花姐' }, { id: 7, name: '小梅' } ] fuzzyQuery(list, '树', 'name') // [{id: 1, name: '树哥'}]
20、遍历树节点
export const foreachTree = (data, callback, childrenName = 'children') => { for (let i = 0; i < data.length; i++) { callback(data[i]) if (data[i][childrenName] && data[i][childrenName].length > 0) { foreachTree(data[i][childrenName], callback, childrenName) } } }
示例:
假设我们要从树状结构数据中查找 id 为 9 的节点
const treeData = [{ id: 1, label: '一级 1', children: [{ id: 4, label: '二级 1-1', children: [{ id: 9, label: '三级 1-1-1' }, { id: 10, label: '三级 1-1-2' }] }] }, { id: 2, label: '一级 2', children: [{ id: 5, label: '二级 2-1' }, { id: 6, label: '二级 2-2' }] }, { id: 3, label: '一级 3', children: [{ id: 7, label: '二级 3-1' }, { id: 8, label: '二级 3-2' }] }], let result foreachTree(data, (item) => { if (item.id === 9) { result = item } }) console.log('result', result) // {id: 9,label: "三级 1-1-1"}