- 作者：陈大鱼头
- github： KRISACHAN
鱼头辛苦总结的15条非常高效的JS技巧，掌握这15个JS技巧，让你减少加班次数，多抽出点时间来陪女（男）朋友。
正文
延迟函数delay
const delay = ms => new Promise((resolve, reject) => setTimeout(resolve, ms))
const getData = status => new Promise((resolve, reject) => {
status ? resolve('done') : reject('fail')
})
const getRes = async (data) => {
try {
const res = await getData(data)
const timestamp = new Date().getTime()
await delay(1000)
console.log(res, new Date().getTime() - timestamp)
} catch (error) {
console.log(error)
}
}
getRes(true)
分割指定长度的元素数组
const listChunk = (list, size = 1, cacheList = []) => {
const tmp = [...list]
if (size <= 0) {
return cacheList
}
while (tmp.length) {
cacheList.push(tmp.splice(0, size))
}
return cacheList
}
console.log(listChunk([1, 2, 3, 4, 5, 6, 7, 8, 9])) // [[1], [2], [3], [4], [5], [6], [7], [8], [9]]
console.log(listChunk([1, 2, 3, 4, 5, 6, 7, 8, 9], 3)) // [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
console.log(listChunk([1, 2, 3, 4, 5, 6, 7, 8, 9], 0)) // []
console.log(listChunk([1, 2, 3, 4, 5, 6, 7, 8, 9], -1)) // []
获取数组交集
const intersection = (list, ...args) => list.filter(item => args.every(list => list.includes(item)))
console.log(intersection([2, 1], [2, 3])) // [2]
console.log(intersection([1, 2], [3, 4])) // []
函数柯里化
const curring = fn => {
const { length } = fn
const curried = (...args) => {
return (args.length >= length
? fn(...args)
: (...args2) => curried(...args.concat(args2)))
}
return curried
}
const listMerge = (a, b, c) => [a, b, c]
const curried = curring(listMerge)
console.log(curried(1)(2)(3)) // [1, 2, 3]
console.log(curried(1, 2)(3)) // [1, 2, 3]
console.log(curried(1, 2, 3)) // [1, 2, 3]
字符串前面空格去除与替换
const trimStart = str => str.replace(new RegExp('^([\\s]*)(.*)$'), '$2')
console.log(trimStart(' abc ')) // abc
console.log(trimStart('123 ')) // 123
字符串后面空格去除与替换
const trimEnd = str => str.replace(new RegExp('^(.*?)([\\s]*)$'), '$1')
console.log(trimEnd(' abc ')) // abc
console.log(trimEnd('123 ')) // 123
获取当前子元素是其父元素下子元素的排位
const getIndex = el => {
if (!el) {
return -1
}
let index = 0
do {
index++
} while (el = el.previousElementSibling);
return index
}
获取当前元素相对于document的偏移量
const getOffset = el => {
const {
top,
left
} = el.getBoundingClientRect()
const {
scrollTop,
scrollLeft
} = document.body
return {
top: top + scrollTop,
left: left + scrollLeft
}
}
获取元素类型
const dataType = obj => Object.prototype.toString.call(obj).replace(/^\[object (.+)\]$/, '$1').toLowerCase();
判断是否是移动端
const isMobile = () => 'ontouchstart' in window
fade动画
const fade = (el, type = 'in') {
el.style.opacity = (type === 'in' ? 0 : 1)
let last = +new Date()
const tick = () => {
const opacityValue = (type === 'in'
? (new Date() - last) / 400
: -(new Date() - last) / 400)
el.style.opacity = +el.style.opacity + opacityValue
last = +new Date()
if (type === 'in'
? (+el.style.opacity < 1)
: (+el.style.opacity > 0)) {
requestAnimationFrame(tick)
}
}
tick()
}
将指定格式的字符串解析为日期字符串
const dataPattern = (str, format = '-') => {
if (!str) {
return new Date()
}
const dateReg = new RegExp(`^(\\d{2})${format}(\\d{2})${format}(\\d{4})$`)
const [, month, day, year] = dateReg.exec(str)
return new Date(`${month}, ${day} ${year}`)
}
console.log(dataPattern('12-25-1995')) // Mon Dec 25 1995 00:00:00 GMT+0800 (中国标准时间)
禁止网页复制粘贴
const html = document.querySelector('html')
html.oncopy = () => false
html.onpaste = () => false
input框限制只能输入中文
const input = document.querySelector('input[type="text"]')
const clearText = target => {
const {
value
} = target
target.value = value.replace(/[^\u4e00-\u9fa5]/g, '')
}
input.onfocus = ({target}) => {
clearText(target)
}
input.onkeyup = ({target}) => {
clearText(target)
}
input.onblur = ({target}) => {
clearText(target)
}
input.oninput = ({target}) => {
clearText(target)
}
去除字符串中的html代码
const removeHTML = (str = '') => str.replace(/<[\/\!]*[^<>]*>/ig, '')
console.log(removeHTML('<h1>哈哈哈哈<呵呵呵</h1>')) // 哈哈哈哈<呵呵呵
后记
以上15个技巧都是我在日常开发中经常用到的一些代码片段，善用这些技巧，可以大大减少我们的开发时间。如果此时正在看文章的你也有类似的技巧心得，不妨在下方留言来分享给大家。