js各类方法记录

获取url指定参数

const getquerys = {
    oa_open_id: "",
    payload: "",
}

function getquery(queryName) {
    var reg = new RegExp("(^|&)" + queryName + "=([^&]*)(&|$)", "i");
    var r = window.location.search.substr(1).match(reg);
    if (r != null) {
        return decodeURI(r[2]);
    } else {
        return null;
    }
}
getquerys.oa_open_id = getquery("oa_open_id");
getquerys.payload = getquery("payload");
export default getquerys;

删除url指定参数

//removeURLParameter(地址,'参数名前缀')
removeURLParameter(url, parameter) {
            var urlparts = url.split("?");
            if (urlparts.length >= 2) {
                //参数名前缀
                var prefix = encodeURIComponent(parameter) + "=";
                var pars = urlparts[1].split(/[&;]/g);

                //循环查找匹配参数
                for (var i = pars.length; i-- > 0; ) {
                    if (pars[i].lastIndexOf(prefix, 0) !== -1) {
                        //存在则删除
                        pars.splice(i, 1);
                    }
                }

                return (
                    urlparts[0] + (pars.length > 0 ? "?" + pars.join("&") : "")
                );
            }
            return url;
        },

清除对象中值为空的属性

//这个方法不会影响原来的对象，而是返回一个新对象
function filterParams(obj) {
    var _newPar = {};
    for (var key in obj) {
        if ((obj[key] === 0 ||obj[key] === false|| obj[key]) && obj[key].toString().replace(/(^\s*)|(\s*$)/g, '') !== '') {
            _newPar[key] = obj[key];
        }
    }
    return _newPar;
}
filterParams({a:"",b:null,c:"010",d:123})       //{c: "010", d: 123}

根据数组中对象的某个属性值进行去重

var arr = [
        {
            from: '张三',
            to: '河南'
        },
        {
            from: '王二',
            to: '阿里'
        },
        {
            from: '王二',
            to: '杭州'
        },
        {
            from: '王二',
            to: '山东'
        },
    ]
    const res = new Map();
    arr = arr.filter((a) => !res.has(a.from) && res.set(a.from, 1))
    console.log(arr);

url操作

getquery(queryName) {
   var reg = new RegExp("(^|&)" + queryName + "=([^&]*)(&|$)", "i");
   var r = window.location.search.substr(1).match(reg);
   if (r != null) {
     return decodeURI(r[2]);
   } else {
     return null;
   }
},

数组去重

function unique(arr) {
  return Array.from(new Set(arr))
}

正则验证

//手机
const phone = ((data) => {
  var myreg = /^1[3456789]\d{9}$/
  if (myreg.test(data)) {
    return true
  } else {
    return false
  }
})

//邮箱
  /^[A-Za-z0-9]+([_\.][A-Za-z0-9]+)*@([A-Za-z0-9\-]+\.)+[A-Za-z]{2,6}$/;

//校验身份证号码
  //15位：
  ^[1-9]\\d{7}((0\\d)|(1[0-2]))(([0|1|2]\\d)|3[0-1])\\d{3}$
  //18位：
  ^[1-9]\\d{5}[1-9]\\d{3}((0\\d)|(1[0-2]))(([0|1|2]\\d)|3[0-1])\\d{3}([0-9]|X)$

//校验日期（“yyyy-mm-dd“ 格式的日期校验，已考虑平闰年。
  ^(?:(?!0000)[0-9]{4}-(?:(?:0[1-9]|1[0-2])-(?:0[1-9]|1[0-9]|2[0-8])|(?:0[13-9]|1[0-2])-(?:29|30)|(?:0[13578]|1[02])-31)|(?:[0-9]{2}(?:0[48]|[2468][048]|[13579][26])|(?:0[48]|[2468][048]|[13579][26])00)-02-29)$

随机获取布尔值（true/false）

const randomBoolean = () => Math.random() >= 0.5;
console.log(randomBoolean());
// Result: a 50/50 change on returning true of false

判断给的日期是否为工作日

const isWeekday = (date) => date.getDay() % 6 !== 0;
console.log(isWeekday(new Date(2021, 0, 11)));
// Result: true (Monday)
console.log(isWeekday(new Date(2021, 0, 10)));
// Result: false (Sunday)

反转字符串

const reverse = str => str.split('').reverse().join('');
reverse('hello world');     
// Result: 'dlrow olleh'

判断当前选项卡是否在视图/焦点中

const isBrowserTabInView = () => document.hidden;
isBrowserTabInView();
// Result: returns true or false depending on if tab is in view / focus

判断数字是偶数还是奇数

const isEven = num => num % 2 === 0;
console.log(isEven(2));
// Result: true
console.log(isEven(3));
// Result: false

从日期获取时间

const timeFromDate = date => date.toTimeString().slice(0, 8);
console.log(timeFromDate(new Date(2021, 0, 10, 17, 30, 0))); 
// Result: "17:30:00"
console.log(timeFromDate(new Date()));
// Result: will log the current time

将数字四舍五入到固定的小数点

const toFixed = (n, fixed) => ~~(Math.pow(10, fixed) * n) / Math.pow(10, fixed);
// Examples
toFixed(25.198726354, 1);       // 25.1
toFixed(25.198726354, 2);       // 25.19
toFixed(25.198726354, 3);       // 25.198
toFixed(25.198726354, 4);       // 25.1987
toFixed(25.198726354, 5);       // 25.19872
toFixed(25.198726354, 6);       // 25.198726

检查元素当前是否处于焦点

const elementIsInFocus = (el) => (el === document.activeElement);
elementIsInFocus(anyElement)
// Result: will return true if in focus, false if not in focus

滚动到页面顶部

const goToTop = () => window.scrollTo(0, 0);
goToTop();
// Result: will scroll the browser to the top of the page

获取参数的平均值

const average = (...args) => args.reduce((a, b) => a + b) / args.length;
average(1, 2, 3, 4);
// Result: 2.5