项目中常用工具函数总结：
1.判断是不是数组
Array.prototype.isPrototypeOf([]) //true
2.判断是否为空值
function isEmpty(val) {
return val === undefined || val === null || val.length === 0 || val === " "
}
3.判断是否为数组
function isArray(obj){
return Object.prototype.toString.call(obj)==="[object Array]"
}
4.日期格式化
function formatDate(time, split) {
const year = time.getFullYear();
const month = time.getMonth() + 1 < 10 ? "0" + (time.getMonth() + 1) : time.getMonth() + 1;
const date = time.getDate() < 10 ? "0" + (time.getDate()) : time.getDate();
return [year,month,date].join(split || "")
}
//调用
let r = formatDate(new Date(),"/")
console.log(r) // 2019/10/29
5.隐藏信息（手机号，身份证等脱敏）
function hideInfo(str, start, end, reverse) {
if (!str) { return str; }
var reStart = 0;
var reEnd = 0;
if (end === null) {
if (!reverse) {
reStart = start;
reEnd = str.length - 1;
} else {
reStart = 0;
reEnd = str.length - start;
}
} else {
if (!reverse) {
reStart = start;
reEnd = end;
} else {
reStart = str.length - end;
reEnd = str.length - start;
}
}
if(reEnd-reStart>=0 && reEnd<str.length){
for(let i = reStart;i<=reEnd;i++){
let temp = str.split("")
temp.splice(i,1,"*");
str=temp.join("")
}
return str
}
if(reEnd>=str.length){
for(var i = reStart;i<str.length;i++){
var temp = str.split("");
temp.splice(i,1,"*");
str = temp.join("")
}
}
return str;
}
6.数字加千分符
function separateThousands(srcNumber) {
if (srcNumber === undefined || srcNumber === null) {
return ""
}
return srcNumber.toString().replace(/^(-?[0-9]+)(?=\.|$)/,function(matchStr){
return matchStr.replace(/([0-9]+?)(?=(?:[0-9]{3})+$)/g,"$1,")
})
}
7.是否是数字
function isNumeric(src){
return src-parseFloat(src) >=0
}
8.是否是一个整数
function isInteger(src){
//先判断是不是数字
if(isNumeric(src)){
if(src.toString().match(/^-?[0-9]+$/)){
return true;
}
}
return false;
}
9.获取对象子集或孙子级的值
function getKey(obj,key){
const keys = key.split(".")
const currentKey = keys.shift();
if(!obj[currentKey]){
return undefined
}
if(!keys.length){
return obj[currentKey]
}
return getKey(obj[currentKey],keys.join("."))
}
getKey({a:100,b:{c:300}},"b.c") //300
10.将两个数组合并为一个对象
let arr1 = ["a","b","c"]
let arr2 = ["hello","world","love"]
let result = arr2.reduce((memo,value,index)=>{
memo[arr1[index]]=value
return memo
},{})
//{a: "hello", b: "world", c: "love"}
