Đã đăng vào Oct 25th, 2015 6:03 a.m. 1 phút đọc

356

Regular Expression template for web development

Bài đăng này đã không được cập nhật trong 4 năm

What is regular expression?

A regular expression is a special text string for describing a search pattern, mainly for use in pattern matching with strings, or string matching.

Regex quick reference

Sample	Definition
`[abc]`	A single character of: a, b, or c
`[^abc]`	Any single character except: a, b, or c
`[a-z]`	Any single character in the range a-z
`[a-zA-Z]`	Any single character in the range a-z or A-Z
`^`	Start of line
`$`	End of line
`\A`	Start of string
`\z`	End of string
`.`	Any single character
`\s`	Any whitespace character
`\S`	Any non-whitespace character
`\d`	Any digit
`\D`	Any non-digit
`\w`	Any word character (letter, number, underscore)
`\W`	Any non-word character
`\b`	Any word boundary
`(...)`	Capture everything enclosed
`(a\|b)`	a or b
`a?`	Zero or one of a
`a*`	Zero or more of a
`a+`	One or more of a
`a{3}`	Exactly 3 of a
`a{3,}`	3 or more of a
`a{3,6}`	Between 3 and 6 of a
options:	i case insensitive m make dot match newlines x ignore whitespace in regex o perform #{...} substitutions only once

The Common regular expression template

1. Email

/\A[\w+\-.]+@[a-z\d\-.]+\.[a-z]+\z/i

Match email:

Don't match email:

user@email.1com
user@email.
user@email
useremail.com

2. Phone number

/^(\+\d{1,2}\s)?\(?\d{3}\)?[\s.-]\d{3}[\s.-]\d{4}$/

Match Phone number

123-456-7890
(123) 456-7890
123 456 7890
123.456.7890
+91 (123) 456-7890

3. HTTP Url

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

Valid URL

Invalid URL

https://viblo
ttps://viblo.asia
//viblo.asia

4. IP Address

/^(?:(?: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]?)$/

Valid IP

192.168.100.1
127.0.0.1
0.0.0.0

Invalid IP

256.123.123.1
192.168.122.
192.168.122

5. Username

/^[a-z0-9_-]{3,32}$/i

Valid username

Jame007
user_Name
like-you

Invalid username

a hacker
me+
you&I

6. Password

/^([a-zA-Z0-9@*#]{6,15})$/

Valid password

password
password123
P@ssw0rd

Invalid password

Hello
My password
no-one-can-guess-my-passord

7. File Extension

([^\s]+(\.(?i)(jpg|png|gif|bmp))$)

Match file

picture.jpg
picture123.png
image.gif

Don't match file

picture.txt
cat-photo.
no-image

8. Time Format

/([01]?[0-9]|2[0-3]):[0-5][0-9]/

Match Time

00:00
22:00
9:00

Don't match time

00:0
24:00
12:65

9. Date Format (dd/mm/yyyy, dd-mm-yyyy)

/^(\d\d)[-\/](\d\d)[-\/](\d\d(?:\d\d)?)$/

Match date

11-02-2015
11/02/2015

Date don't match

12-Feb-1222
2-1-15

Try online: http://rubular.com/

Regular expression (RegExp)