欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页  >  IT编程

10个非常实用的JS工具函数

程序员文章站 2022-06-19 16:25:49
JS工具函数生成一周时间类型判断对象属性剔除数组去重日期格式化防抖节流base64数据导出文件下载检测是否为PC端浏览器识别浏览器及平台获取系统根路径生成一周时间function getWeekTime(){ return [...new Array(7)].map((j,i)=> new Date(Date.now()+i*8.64e7).toLocaleDateString())}类型判断/** * @param {any} target * @param {string} t...

生成一周时间

function getWeekTime(){
  return [...new Array(7)].map((j,i)=> new Date(Date.now()+i*8.64e7).toLocaleDateString())
}

类型判断

/**
 * @param {any} target
 * @param {string} type
 * @return {boolean}
 */
function isType(target, type) {
  let targetType = Object.prototype.toString.call(target).slice(8, -1).toLowerCase()
  return targetType === type.toLowerCase()
}
isType([], 'Array') // true
isType(/\d/, 'RegExp') // true
isType(new Date(), 'Date') // true
isType(function(){}, 'Function') // true
isType(Symbol(1), 'Symbol') // true

对象属性剔除

/**
 * @param {object} object
 * @param {string[]} props
 * @return {object}
 */
function omit(object, props=[]){
  let res = {}
  Object.keys(object).forEach(key=>{
    if(props.includes(key) === false){
      res[key] = typeof object[key] === 'object' && object[key] !== null ?
        jsON.parse(jsON.stringify(object[key])):
        object[key]
    }
  })
  return res
}

数组去重

/**
 * 
 * @desc 数组去重
 * @param {Array} arr
 */
function removeDupthird(arr) {
    var newArr = [];
    var obj = {};
    for (var i = 0; i < arr.length; i++) {
        obj[arr[i]] = arr[i];
    }
    var list = [];
    for ( var i in obj) {
        list.push(i);
    }
    return list;
};
let data = {
  id: 1,
  title: 'xxx',
  comment: []
}
omit(data, ['id']) // {title: 'xxx', comment: []}

日期格式化

/**
 * @param {string} format
 * @param {number} timestamp - 时间戳
 * @return {string}
 */
function formatDate(format='Y-M-D h:m', timestamp=Date.now()){
  let date = new Date(timestamp)
  let dateInfo = {
    Y: date.getFullYear(),
    M: date.getMonth()+1,
    D: date.getDate(),
    h: date.getHours(),
    m: date.getMinutes(),
    s: date.getSeconds()
  }
  let formatNumber = (n) => n > 10 ? n : '0' + n
  let res = format
    .replace('Y', dateInfo.Y)
    .replace('M', dateInfo.M)
    .replace('D', dateInfo.D)
    .replace('h', formatNumber(dateInfo.h))
    .replace('m', formatNumber(dateInfo.m))
    .replace('s', formatNumber(dateInfo.s))
  return res
}
formatDate() // "2020-2-24 13:44"
formatDate('M月D日 h:m') // "2月24日 13:45"
formatDate('h:m Y-M-D', 1582526221604) // "14:37 2020-2-24"

防抖

function debounce(func, wait = 300){
  let timer = null;
  return function(){
    if(timer !== null){
      clearTimeout(timer);
    }
    timer = setTimeout(fn,wait);
  }
}
/**
 * @param {function} func - 执行函数
 * @param {number} wait - 等待时间
 * @param {boolean} immediate - 是否立即执行
 * @return {function}
 */
function debounce(func, wait = 300, immediate = false){
  let timer, ctx;
  let later = (arg) => setTimeout(()=>{
    func.apply(ctx, arg)
    timer = ctx = null
  }, wait)
  return function(...arg){
    if(!timer){
      timer = later(arg)
      ctx = this
      if(immediate){
        func.apply(ctx, arg)
      }
    }else{
      clearTimeout(timer)
      timer = later(arg)
    }
  }
}
// 使用
let scrollHandler = debounce(function(e){
  console.log(e)
}, 500)
window.onscroll = scrollHandler

节流

/**
 * @param {function} func - 执行函数
 * @param {number} delay - 延迟时间
 * @return {function}
 */
function throttle(func, delay){
  let timer = null
  return function(...arg){
    if(!timer){
      timer = setTimeout(()=>{
        func.apply(this, arg)
        timer = null
      }, delay)
    }
  }
}
let scrollHandler = throttle(function(e){
  console.log(e)
}, 500)
window.onscroll = scrollHandler

base64数据导出文件下载

/**
 * @param {string} filename - 下载时的文件名
 * @param {string} data - base64字符串
 */
function downloadFile(filename, data){
  let downloadLink = document.createElement('a');
  if ( downloadLink ){
    document.body.appendChild(downloadLink);
    downloadLink.style = 'display: none';
    downloadLink.download = filename;
    downloadLink.href = data;
    if ( document.createEvent ){
      let downloadEvt = document.createEvent('MouseEvents');
      downloadEvt.initEvent('click', true, false);
      downloadLink.dispatchEvent(downloadEvt);
    } else if ( document.createEventObject ) {
      downloadLink.fireEvent('onclick');
    } else if (typeof downloadLink.onclick == 'function' ) {
      downloadLink.onclick();
    }
    document.body.removeChild(downloadLink);
  }
}

检测是否为PC端浏览器

function isPCBroswer() {
  let e = window.navigator.userAgent.toLowerCase()
    , t = "ipad" == e.match(/ipad/i)
    , i = "iphone" == e.match(/iphone/i)
    , r = "midp" == e.match(/midp/i)
    , n = "rv:1.2.3.4" == e.match(/rv:1.2.3.4/i)
    , a = "ucweb" == e.match(/ucweb/i)
    , o = "android" == e.match(/android/i)
    , s = "windows ce" == e.match(/windows ce/i)
    , l = "windows mobile" == e.match(/windows mobile/i);
  return !(t || i || r || n || a || o || s || l)
}

识别浏览器及平台

function getPlatformInfo(){
  //运行环境是浏览器
  let inBrowser = typeof window !== 'undefined';
  //运行环境是微信
  let inWeex = typeof WXEnvironment !== 'undefined' && !!WXEnvironment.platform;
  let weexPlatform = inWeex && WXEnvironment.platform.toLowerCase();
  //浏览器 UA 判断
  let UA = inBrowser && window.navigator.userAgent.toLowerCase();
  if(UA){
    let platforms = {
      IE: /msie|trident/.test(UA),
      IE9: UA.indexOf('msie 9.0') > 0,
      Edge: UA.indexOf('edge/') > 0,
      Android: UA.indexOf('android') > 0 || (weexPlatform === 'android'),
      IOS: /iphone|ipad|ipod|ios/.test(UA) || (weexPlatform === 'ios'),
      Chrome: /chrome\/\d+/.test(UA) && !(UA.indexOf('edge/') > 0),
    }
    for (const key in platforms) {
      if (platforms.hasOwnProperty(key)) {
        if(platforms[key]) return key
      }
    }
  }
}

获取系统根路径

/**
 * @desc 获取系统根路径
 */
function getRootPath() {
    // 获取当前网址,如: http://localhost:8083/uimcardprj/share/meun.jsp
    var curWwwPath = window.document.location.href;
    // 获取主机地址之后的目录,如: uimcardprj/share/meun.jsp
    var pathName = window.document.location.pathname;
    var pos = curWwwPath.indexOf(pathName);
    // 获取主机地址,如: http://localhost:8083
    var localhostPaht = curWwwPath.substring(0, pos);
    // 获取带"/"的项目名,如:/uimcardprj
    var projectName = pathName.substring(0, pathName.substring(1).indexOf('/') + 1);
    //return (localhostPaht + projectName + "/");
    return (localhostPaht);
}

本文地址:https://blog.csdn.net/qq_28875189/article/details/107466581