js常见的全局方法还不来了解一下？

globalApproach.js

按需引入：

import {XXX} from "globalApproach.js"

全局引入:

import  "globalApproach.js"

/**
 * 获取hash参数
 */
export const getHashParameter =(name)=> {
  var reg = new RegExp('(^|&)' + name + '=([^&]*)(&|$)', 'i');
  var url = decodeURIComponent(window.location.hash).split('?')[1];
  if(url){
    var r = url.match(reg);
  }
  if(r) {
    return decodeURIComponent(r[2]);
  }
  return null;
}


/**
 * 获取url参数
 */
export const getQueryVariable = (variable)=>
{
    var query = decodeURIComponent(window.location.search.substring(1));
    var vars = query.split("&");
    for (var i=0;i<vars.length;i++) {
        var pair = vars[i].split("=");
        if(pair[0] == variable){
          return pair[1];
        }
    }
    return false;
}


/**
 * 将date转为 格式化  yyyy-mm-dd / HH:ss:mm
 */
export function formatDate (date, format) {
  if (!date) return
  if (!format)
    format = 'yyyy-MM-dd'
  switch (typeof date) {
    case 'string':
      date = new Date(date.replace(/-/, '/'))
      break
    case 'number':
      date = new Date(date)
      break
  }
  if (!date instanceof Date) return
  var dict = {
    'yyyy': date.getFullYear(),
    'M': date.getMonth() + 1,
    'd': date.getDate(),
    'H': date.getHours(),
    'm': date.getMinutes(),
    's': date.getSeconds(),
    'MM': ('' + (date.getMonth() + 101)).substr(1),
    'dd': ('' + (date.getDate() + 100)).substr(1),
    'HH': ('' + (date.getHours() + 100)).substr(1),
    'mm': ('' + (date.getMinutes() + 100)).substr(1),
    'ss': ('' + (date.getSeconds() + 100)).substr(1)
  }
  return format.replace(/(yyyy|MM?|dd?|HH?|ss?|mm?)/g, function () {
    return dict[arguments[0]]
  })
}


/**
 * 获取两个日期之间的天数
 */
export function getDaysNum(strDateStart,strDateEnd){
     let strSeparator = "-"; //日期分隔符
     let oDate1;
     let oDate2;
     let iDays;
     oDate1= strDateStart.split(strSeparator);
     oDate2= strDateEnd.split(strSeparator);
     let strDateS = new Date(oDate1[0], oDate1[1]-1, oDate1[2]);
     let strDateE = new Date(oDate2[0], oDate2[1]-1, oDate2[2]);
     iDays = parseInt(Math.abs(strDateS - strDateE ) / 1000 / 60 / 60 /24);//把相差的毫秒数转换为天数
     return iDays ;
  }



/**
 * 对象数组属性排序（与快排时间复杂度差不多）
 */
export function compareSort(key,arr,order){
    return arr.sort((value1,value2)=>{
        var val1 = value1[key];
          var val2 = value2[key];
          if(order == 'down'){
            return val2-val1;
          }
          if(order == 'up'){
            return val1-val2;
          }
    })
}