收集常用工具函数，拿来即用

2018-03-24

一些常用的工具函数

url地址对象解析

function parseQueryString(url){  
    var result={};  
    var params=url.split("?")[1].split("&");  
    for(var i=0,length=params.length;i<length;i++){  
        var temp=params[i].split("=");  
        result[temp[0]]=temp[1];  
    }  
    return result;

生成随机密码

function randomPassword(size) {
  var seed = ["A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z", "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "m", "n", "p", "Q", "r", "s", "t", "u", "v", "w", "x", "y", "z", "2", "3", "4", "5", "6", "7", "8", "9"];
  const seedlength = seed.length;
  let createPassword = '';
  for (let i = 0; i < size; i++) {
    const j = Math.floor(Math.random() * seedlength);
    createPassword += seed[j];
  }
  return createPassword;
}

randomPassword(5)
// 输出："a5Csy"

判断时间间隔（几天前）

传入的参数为需要判断的时间戳（毫秒）

function dateStr(date){
    //获取js 时间戳
    var time=new Date().getTime();
    time=parseInt((time-date*1000)/1000);

    //存储转换值
    var s;
    if(time<60*10){//十分钟内
        return '刚刚';
    }else if((time<60*60)&&(time>=60*10)){
        //超过十分钟少于1小时
        s = Math.floor(time/60);
        return  s+"分钟前";
    }else if((time<60*60*24)&&(time>=60*60)){ 
        //超过1小时少于24小时
        s = Math.floor(time/60/60);
        return  s+"小时前";
    }else if((time<60*60*24*3)&&(time>=60*60*24)){ 
        //超过1天少于3天内
        s = Math.floor(time/60/60/24);
        return s+"天前";
    }else{ 
        //超过3天
        var date= new Date(parseInt(date) * 1000);
        return date.getFullYear()+"/"+(date.getMonth()+1)+"/"+date.getDate();
    }
}
dateStr(1521697302999)
// 输出 "刚刚"

时间日期格式化

date参数为待格式化的日期字符串
参数format为格式化格式默认为yyyy-MM-dd hh:mm:ss

return a.toString().replace(/^(\d)$/,”0$1”)

如果a是一位数，则在前面加0
1—->01

function dateFmt(date, format) {
  if (!date) return '';
  date = new Date(date);
  const paddNum = function (num) {
      num += ''
      return num.replace(/^(\d)$/, '0$1')
    }
    // 指定格式字符
  const cfg = {
    yyyy: date.getFullYear(),
    yy: date.getFullYear().toString().substring(2),
    M: date.getMonth() + 1,
    MM: paddNum(date.getMonth() + 1),
    d: date.getDate(),
    dd: paddNum(date.getDate()),
    hh: paddNum(date.getHours()),
    mm: paddNum(date.getMinutes()),
    ss: paddNum(date.getSeconds())
  }
  format || (format = 'yyyy-MM-dd hh:mm:ss')
  return format.replace(/([a-z])(\1)*/ig, function (m) {
    return cfg[m]
  })
}


dateFmt(1521697721522,'yyyy-MM-dd')
// 输出： "2018-03-22"
dateFmt(1521697721522,'hh:mm:ss')
// 输出  "13:48:41"

判断日期是否为今天

基于上例的格式化函数dateFmt()

function isToday(str) {
  var date = str && new Date(str);
  date = dateFmt(date, 'yyyy-MM-dd');
  var now = new Date();
  var y = now.getFullYear();
  var m = (now.getMonth() + 1) < 10 ? '0' + (now.getMonth() + 1) : (now.getMonth() + 1);
  var d = now.getDate() < 10 ? '0' + now.getDate() : now.getDate();
  var today = y + '-' + m + '-' + d;
  return today === date;
}

数字转金额

参数s为待转换的金额

n为需要保留的小数

function currencyFmt(s, n) {
  n = n > 0 && n <= 20 ? n : 2;
  if (!s && s !== 0) {
    return '';
  }
  s = parseFloat((s + '').replace(/[^\d\.-]/g, '')).toFixed(n) + '';
  var l = s.split('.')[0],
    r = s.split('.')[1];
  return '\u00a5' + ' ' + l + '.' + r;
}

currencyFmt(123.2568,3)
// 输出 "¥ 123.257"