With these 25 regular expressions, the code efficiency is increased by 80%

Preface

Hello everyone, I’m Lin Sanxin. In daily development, the regular expression is very useful, and the regular expression can be used in every language. It is the JSON . It is universal. In daily development, understanding some commonly used regular expressions can greatly improve your work efficiency, such as

String matching
Format verification of form items

Today I will share with you 25 regular expressions commonly used in development! ! ! I hope everyone can improve code efficiency! ! !

`1. Verification of mobile phone number`

const phoneReg = /^[1][3,4,5,6,7,8,9][0-9]{9}$/

const phoneStr1 = '18886233487'
console.log(phoneReg.test(phoneStr1)) // true

const phoneStr2 = '17283017203897'
console.log(phoneReg.test(phoneStr2)) // false

`2. ID card verification`

const sfzReg = /^[1-9]\d{5}(18|19|([23]\d))\d{2}((0[1-9])|(10|11|12))(([0-2][1-9])|10|20|30|31)\d{3}[0-9Xx]$/

const sfzStr1 = '415106199801012130'
console.log(sfzReg.test(sfzStr1)) // true

const sfzStr2 = '718381298381212183'
console.log(sfzReg.test(sfzStr2)) // false

`3. Mailbox verification`

const emailReg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/

const emailStrWY = '956666@163.com' // 163邮箱
const emailStrQQ = '956666@qq.com' // qq邮箱
console.log(emailReg.test(emailStrWY)) // true
console.log(emailReg.test(emailStrQQ)) // true

const noEmail = '72873213.com'
console.log(emailReg.test(noEmail)) // false

`4. URL verification`

const urlReg = /^((https?|ftp|file):\/\/)?([\da-z\.-]+)\.([a-z\.]{2,6})([\/\w \.-]*)*\/?$/

const urlStr1 = 'https://haha.sunshine.com/xxx/xxx'
console.log(urlReg.test(urlStr1)) // true

const urlStr2 = 'sss://haha.sunshine.com/xxx/xxx'
console.log(urlReg.test(urlStr2)) // false

`5. IPv4 verification`

const ipv4Reg = /^(?:(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(?:25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$/

const ipv4Str1 = '122.12.56.65'
console.log(ipv4Reg.test(ipv4Str1)) // true

const ipv4Str2 = '122.12.56.655'
console.log(ipv4Reg.test(ipv4Str2)) // false

`6, hexadecimal color verification`

const color16Reg = /^#?([a-fA-F0-9]{6}|[a-fA-F0-9]{3})$/

const color16Str1 = '#fff'
console.log(color16Reg.test(color16Str1)) // true

const color16Str2 = '#1234567'
console.log(color16Reg.test(color16Str2)) // false

`7. Date YYYY-MM-DD`

const dateReg = /^\d{4}(\-)\d{1,2}\1\d{1,2}$/

const dateStr1 = '2021-10-10'
console.log(dateReg.test(dateStr1)) // true

const dateStr2 = '2021-01-01 1'
console.log(dateReg.test(dateStr2)) // false

`8. Date YYYY-MM-DD hh:mm:ss`

const dateReg = /^(\d{1,4})(-|\/)(\d{1,2})\2(\d{1,2}) (\d{1,2}):(\d{1,2}):(\d{1,2})$/

const dateStr1 = '2021-10-10 16:16:16'
console.log(dateReg.test(dateStr1)) // true

const dateStr2 = '2021-10-10 16:'
console.log(dateReg.test(dateStr2)) // false

`9. Integer check`

const intReg = /^[-+]?\d*$/

const intNum1 = 12345
console.log(intReg.test(intNum1)) // true

const intNum2 = 12345.1
console.log(intReg.test(intNum2)) // false

`10. Check of decimals`

const floatReg = /^[-\+]?\d+(\.\d+)?$/

const floatNum = 1234.5
console.log(floatReg.test(floatNum)) // true

`11. Keep n decimal places`

function checkFloat(n) {
  return new RegExp(`^([1-9]+[\d]*(.[0-9]{1,${n}})?)$`)
}
// 保留2位小数
const floatReg = checkFloat(2)

const floatNum1 = 1234.5
console.log(floatReg.test(floatNum1)) // true

const floatNum2 = 1234.55
console.log(floatReg.test(floatNum2)) // true

const floatNum3 = 1234.555
console.log(floatReg.test(floatNum3)) // false

`12. Verification of postal code`

const postalNoReg = /^\d{6}$/

const postalNoStr1 = '522000'
console.log(postalNoReg.test(postalNoStr1)) // true

const postalNoStr2 = '5220000'
console.log(postalNoReg.test(postalNoStr2)) // false

`13, QQ number verification`

Description: 5-11 digits

const qqReg = /^[1-9][0-9]{4,10}$/

const qqStr1 = '1915801633'
console.log(qqReg.test(qqStr1)) // true

const qqStr2 = '191580163333'
console.log(qqReg.test(qqStr2)) // false

`14. Wechat verification`

Description: 6 to 20 digits, starting with a letter, letter, number, minus sign, underscore

const wxReg = /^[a-zA-Z]([-_a-zA-Z0-9]{5,19})+$/

const wxStr1 = 'linsanxin885577'
console.log(wxReg.test(wxStr1)) // true

const wxStr2 = '厉害了我的vx'
console.log(wxReg.test(wxStr2)) // false

`15. Verification of license plate number`

const carNoReg = /^[京津沪渝冀豫云辽黑湘皖鲁新苏浙赣鄂桂甘晋蒙陕吉闽贵粤青藏川宁琼使领A-Z]{1}[A-Z]{1}[A-Z0-9]{4}[A-Z0-9挂学警港澳]{1}$/

const carNoStr1 = '粤A12345'
console.log(carNoReg.test(carNoStr1)) // true

const carNoStr2 = '广东A12345'
console.log(carNoReg.test(carNoStr2)) // false

`16. Strings containing only letters`

const letterReg = /^[a-zA-Z]+$/

const letterStr1 = 'sunshineLin'
console.log(letterReg.test(letterStr1)) // true

const letterStr2 = 'sunshine_Lin'
console.log(letterReg.test(letterStr2)) // false

`17. Strings containing Chinese`

const cnReg = /[\u4E00-\u9FA5]/

const cnStr1 = '我是sunshine_Lin，林三心'
console.log(cnReg.test(cnStr1)) // true

const cnStr2 = 'sunshine_Lin'
console.log(cnReg.test(cnStr2)) // false

`18. Password strength verification`

Note: The password must contain letters, numbers, special characters, at least 8 characters, and a maximum of 30 characters

const passwordReg = /(?=.*[0-9])(?=.*[a-zA-Z])(?=.*[^a-zA-Z0-9]).{8,30}/

const password1 = 'sunshine_Lin12345..'
console.log(passwordReg.test(password1)) // true

const password2 = 'sunshineLin12345'
console.log(passwordReg.test(password2)) // false

`19. Verification of string length n`

function checkStrLength(n) {
  return new RegExp(`^.{${n}}$`)
}

// 校验长度为3的字符串
const lengthReg = checkStrLength(3)

const str1 = 'hhh'
console.log(lengthReg.test(str1)) // true

const str2 = 'hhhhh'
console.log(lengthReg.test(str2)) // false

`20. Verification of file extension`

function checkFileName (arr) {
  arr = arr.map(name => `.${name}`).join('|')
  return new RegExp(`(${arr})$`)
}

const filenameReg = checkFileName(['jpg', 'png', 'txt'])

const filename1 = 'sunshine.jpg'
console.log(filenameReg.test(filename1)) // true
const filename2 = 'sunshine.png'
console.log(filenameReg.test(filename2)) // true
const filename3 = 'sunshine.txt'
console.log(filenameReg.test(filename3)) // true
const filename4 = 'sunshine.md'
console.log(filenameReg.test(filename4)) // false

`21, match img and src`

const imgReg = /<img.*?src=[\"|\']?(.*?)[\"|\']?\s.*?>/ig

const htmlStr = '<div></div><img src="sunshine.png" /><img src="sunshine111.png" />'

console.log(imgReg.exec(htmlStr))
// [
//   '<img src="sunshine.png" />',
//   'sunshine.png',
//   index: 11,
//   input: '<div></div><img src="sunshine.png" /><img src="sunshine111.png" />',
//   groups: undefined
// ]
console.log(imgReg.exec(htmlStr))
// [
//   '<img src="sunshine111.png" />',
//   'sunshine111.png',
//   index: 37,
//   input: '<div></div><img src="sunshine.png" /><img src="sunshine111.png" />',
//   groups: undefined
// ]

`22. Match comments in html`

const noteReg = /<!--(.*?)-->/g

const htmlStr = '<!--一个div标签--> <div></div> <!--一个div标签--> <div></div>'

console.log(noteReg.exec(htmlStr))
// [
//   '<!--一个div标签-->',
//   '一个div标签',
//   index: 0,
//   input: '<!--一个div标签--> <div></div> <!--一个div标签--> <div></div>',
//   groups: undefined
// ]
console.log(noteReg.exec(htmlStr))
// [
//   '<!--一个div标签-->',
//   '一个div标签',
//   index: 27,
//   input: '<!--一个div标签--> <div></div> <!--一个div标签--> <div></div>',
//   groups: undefined
// ]

`23, match the style in html`

const styleReg = /style="[^=>]*"([(\s+\w+=)|>])/g

const htmlStr = '<div style="background:#000;"><span style="color:#fff"></span></div>'

console.log(styleReg.exec(htmlStr))
// [
//   'style="background:#000;">',
//   '>',
//   index: 5,
//   input: '<div style="background:#000;"><span style="color:#fff"></span></div>',
//   groups: undefined
// ]
console.log(styleReg.exec(htmlStr))
// [
//   'style="color:#fff">',
//   '>',
//   index: 36,
//   input: '<div style="background:#000;"><span style="color:#fff"></span></div>',
//   groups: undefined
// ]

`24, match the color in html`

const colorReg = /#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})/g

const htmlStr = '<div style="background:#000;"><span style="color:#fff"></span></div>'

console.log(colorReg.exec(htmlStr))
// [
//   '#000',
//   '000',
//   index: 23,
//   input: '<div style="background:#000;"><span style="color:#fff"></span></div>',
//   groups: undefined
// ]
console.log(colorReg.exec(htmlStr))
// [
//   '#fff',
//   'fff',
//   index: 49,
//   input: '<div style="background:#000;"><span style="color:#fff"></span></div>',
//   groups: undefined
// ]

`25. Match htmlTag (html tag)`

const endReg = /<("[^"]*"|'[^']*'|[^'">])*>/g

const htmlStr = '<div style="background:#000;"><span style="color:#fff"></span></div><h1></h1>'

console.log(endReg.exec(htmlStr))
console.log(endReg.exec(htmlStr))
console.log(endReg.exec(htmlStr))
console.log(endReg.exec(htmlStr))
console.log(endReg.exec(htmlStr))
console.log(endReg.exec(htmlStr))

`Concluding remarks`

If you think this article is of little help to you, please give me a thumbs up and encourage Lin Sanxin haha. Or you can join my fish-fishing group. Let's study hard together, ah, ah, ah, ah, I will mock interviews regularly, resume guidance, answer questions and answer questions, let's learn from each other and make progress together! !