25 个 JavaScript 杀手级语句，让你看起来像个专业人士

const copyToClipboard = (content) => navigator.clipboard.writeText(content)


copyToClipboard("Hello fatfish")
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const getSelectedText = () => window.getSelection().toString()


getSelectedText()
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const shuffleArray = array => array.sort(() => Math.random() - 0.5)


shuffleArray([ 1, 2,3,4, -1, 0 ]) // [3, 1, 0, 2, 4, -1]
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const rgbaToHex = (r, g, b) => "#" + [r, g, b].map(num => parseInt(num).toString(16).padStart(2, '0')).join('')


rgbaToHex(0, 0 ,0) // #000000
rgbaToHex(255, 0, 127) //#ff007f
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const hexToRgba = hex => {
  const [r, g, b] = hex.match(/\w\w/g).map(val => parseInt(val, 16))
  return `rgba(${r}, ${g}, ${b}, 1)`;
}


hexToRgba('#000000') // rgba(0, 0, 0, 1)
hexToRgba('#ff007f') // rgba(255, 0, 127, 1)
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const average = (...args) => args.reduce((a, b) => a + b, 0)


average(0, 1, 2, -1, 9, 10) // 3.5
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const isEven = num => num % 2 === 0


isEven(2) // true
isEven(1) // false
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const uniqueArray = (arr) => [...new Set(arr)]


uniqueArray([ 1, 1, 2, 3, 4, 5, -1, 0 ]) // [1, 2, 3, 4, 5, -1, 0]
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const isEmpty = obj => Reflect.ownKeys(obj).length === 0 && obj.constructor === Object


isEmpty({}) // true
isEmpty({ name: 'fatfish' }) // false
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const reverseStr = str => str.split('').reverse().join('')


reverseStr('fatfish') // hsiftaf
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const dayDiff = (d1, d2) => Math.ceil(Math.abs(d1.getTime() - d2.getTime()) / 86400000)


dayDiff(new Date("2023-06-23"), new Date("1997-05-31")) // 9519
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const dayInYear = (d) => Math.floor((d - new Date(d.getFullYear(), 0, 0)) / 1000 / 60 / 60 / 24)


dayInYear(new Date('2023/06/23'))// 174
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const capitalize = str => str.charAt(0).toUpperCase() + str.slice(1)


capitalize("hello fatfish")  // Hello fatfish
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const generateRandomString = length => [...Array(length)].map(() => Math.random().toString(36)[2]).join('')


generateRandomString(12) // cysw0gfljoyx
generateRandomString(12) // uoqaugnm8r4s
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const random = (min, max) => Math.floor(Math.random() * (max - min + 1) + min)


random(1, 100) // 27
random(1, 100) // 84
random(1, 100) // 55
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const round = (n, d) => Number(Math.round(n + "e" + d) + "e-" + d)


round(3.1415926, 3) //3.142
round(3.1415926, 1) //3.1
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const clearCookies = document.cookie.split(';').forEach(cookie => document.cookie = cookie.replace(/^ +/, '').replace(/=.*/, `=;expires=${new Date(0).toUTCString()};path=/`))
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const isDarkMode = window.matchMedia && window.matchMedia('(prefers-color-scheme: dark)').matches


console.log(isDarkMode)
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const goToTop = () => window.scrollTo(0, 0)


goToTop()
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const isAppleDevice = () => /Mac|iPod|iPhone|iPad/.test(navigator.platform)


isAppleDevice()
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const randomBoolean = () => Math.random() >= 0.5


randomBoolean()
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const typeOf = (obj) => Object.prototype.toString.call(obj).slice(8, -1).toLowerCase()


typeOf('')     // string
typeOf(0)      // number
typeOf()       // undefined
typeOf(null)   // null
typeOf({})     // object
typeOf([])     // array
typeOf(0)      // number
typeOf(() => {})  // function
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const checkTabInView = () => !document.hidden
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const isFocus = (ele) => ele === document.activeElement
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const generateRandomIP = () => {
  return Array.from({length: 4}, () => Math.floor(Math.random() * 256)).join('.');
}


generateRandomIP() // 220.187.184.113
generateRandomIP() // 254.24.179.151
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