一个随时更新的js库

1.src同级建commFunction=》timer.js

2.main.js引入

import time from '../commonFunction/time'
Vue.prototype.time=time

=======================================

情况一1.时间戳

// 时间戳转时间 2020-4-24 00:30:00

    timeStamp(val) {
        val = val.toString()
        if(val.length == 10) {
          let time = val * 1000;
          let timestamp4 = new Date(time);
          return (timestamp4.toLocaleDateString().replace(/\//g, "-") +" " + timestamp4.toTimeString().substr(0, 8));
        } else {
          let timestamp4 = new Date(val);
          return (timestamp4.toLocaleDateString().replace(/\//g, "-") +" " +timestamp4.toTimeString().substr(0, 8));
        }
    },
    // 2017-4-8 14:11:33转2017-04-08 14:11:33
    handeldate(m){
        let o = m[0]+m[1]+m[2]+m[3]
        if(m.length==18){
            if(m[6]=='-'){
                return o+m[4]+'0'+m[5]+m[6]+m[7]+m[8]+m.slice(9)
            }
            if(m[7]=='-'){
                return o+m[4]+m[5]+m[6]+m[7]+'0'+m[8]+m.slice(9)
            }
        }else if(m.length==17){
            return o+m[4]+'0'+m[5]+m[6]+'0'+m[7]+m.slice(8)
        }else{
            return m
        }
    }

页面使用：

appList.forEach(element => {
     element.create_time = this.time.handeldate(this.time.timeStamp(element.create_time))
});

=======================================

二，生成订单号HWsdAjkFlvh...152652366（后边是时间戳，头部可自定义）

createOrder(){
        //当前时间戳
        let stamp = Date.parse(new Date()).toString()
        let orderEnd = ''
        let letter = 'A,B,C,E,F,G,H,J,K,L,M,N,P,Q,R,S,T,W,X,Y,Z,1,2,3,4,5,6,7,8,9,0,q,w,e,r,t,y,u,i,o,p,a,s,d,f,g,h,j,k,l,z,x,c,v,b,n,m'
        let letterStr = letter.split(',')
        let letLength = letterStr.length
        //设置订单号后半截随机的长度
        for(let i=0;i<10;i++){
            orderEnd+=letterStr[this.randomNum(0,letLength-1)]
        }
        return 'HW'+orderEnd+stamp.substr(0,10)
    },

    //随机数0-n

    randomNum(minNum,maxNum){ 

        switch(arguments.length){ 

            case 1: 

                return parseInt(Math.random()*minNum+1,10); 

            break; 

            case 2: 

                return parseInt(Math.random()*(maxNum-minNum+1)+minNum,10); 

            break; 

                default: 

                    return 0; 

                break; 

        } 

    },

=======================================

三，生成6位随机码8b1BQl（需要上边的随机数方法）

createShortLink(){
        let shortLink = ''
        let letter = 'A,B,C,E,F,L,M,N,P,Q,R,S,T,W,X,Y,Z,1,2,3,4,5,6,7,8,9,0,q,a,e,r,t,y,u,o,p,g,h,j,k,l,x,b,n,m,1,2,3,4,5,6,7,8,9,0'
        let letterStr = letter.split(',')
        let letLength = letterStr.length
        for(let i=0;i<6;i++){
            shortLink+=letterStr[this.randomNum(0,letLength-1)]
        }
        return shortLink
    }

=======================================

四，做echart图表的几个跟日期有关的方法

//输出相同元素的个数

export function unique (arr) {

        var resultObj = {};

        var result = [];

        var result2 = [];

        for(var i=0; i<arr.length; i++){

        if(result.indexOf(arr[i]) == -1){

            result.push(arr[i]);

        }else{

            if(result2.indexOf(arr[i]) == -1){

                result2.push(arr[i]);

        }

        }

        }

        var obj = {}

        arr.forEach((v,k)=>{

        if(obj[v]){

            obj[v]++;

        }else{

            obj[v] = 1;

        }

        });

        resultObj.result = result;

        resultObj.result2 = result2;

        resultObj.obj = obj;

        return {resultObj}

    }

//获取最近day天日期数组,含今天（x横坐标）

export function getBeforeDateLineX(day){

    var ot = new Date().getTime(),

        da = [],

        nd,

        month,

        day;

        for(var i=day-1;i>-1;i--){

            nd = ot - i*24*60*60*1000;

            month = new Date(nd).getMonth()+1,

            day = new Date(nd).getDate();

            da.push(month+'.'+day);

        }

      return da;

}

//获取最近n天的两个端点时间戳,当前时刻至n天前的当前时刻(含今天，即时)

export function getTimePoint(n){

    let value1 = []

    let dateToDay = parseInt(new Date().getTime()/1000)

    value1[0] = dateToDay - n*24*60*60

    value1[1] = dateToDay

    return value1

}

//获取最近n天的两个端点时间戳,当前天至n天前(不含今天，整点)

export function getTimePointZero(n){

    let today = new Date();

    let dateToDay =  parseInt(new Date(today.toDateString()).getTime()/1000);

    let value1 = []

    value1[0] = dateToDay - n*24*60*60

    value1[1] = dateToDay

    return value1

}

//获取前第n天的初末时刻

export function beforeYesterdayZero(n){

    let today = new Date();

    let dateToDay =  parseInt(new Date(today.toDateString()).getTime()/1000);

    let value1 = []

    value1[0] = dateToDay - n*24*60*60

    value1[1] = dateToDay - (n-1)*24*60*60

    return value1

}

//获取最近日期数组,可不含今天（x横坐标）参数是某两天00:00的10位时间戳

export function getGroupDateLineX(tZero1,tZero2){

    let a = tZero1

    let arrStamps = [tZero1]

    for(let i=0;i<100;i++){

        if(a<tZero2){

            a+=24*60*60

            arrStamps.push(a)

        }

    }

    return arrStamps

}

//输出数组相同元素个数

export function getCount(arr,rank,ranktype){

    var obj = {}, k, arr1 = [];

    for (var i = 0, len = arr.length; i < len; i++) {

        k = arr[i];

        if (obj[k]) 

            obj[k]++;

        else 

            obj[k] = 1;

    }

    //保存结果{el-'元素'，count-出现次数}

    for (var o in obj) {

        arr1.push({el: o, count: obj[o]});

    }

    //排序（降序）

    arr1.sort(function (n1, n2) {

        return n2.count - n1.count

    });

    //如果ranktype为1，则为升序，反转数组

    if(ranktype===1){

        arr1=arr1.reverse();

    }

    var rank1 = rank || arr1.length;

    return arr1.slice(0,rank1);

}