Regular Expressions 101

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Community Patterns

1

Extract URL, FTP, Mailto

ECMAScript (JavaScript)
extract url such as http, https:, ftp and mailto from a string
Submitted by Kumar Sundaram - 8 years ago
1

Months Regex

ECMAScript (JavaScript)
For Month Verification Works for January / Jan / Jan.
Submitted by F0123X - 8 years ago
1

Password minimum requirements

PCRE (PHP <7.3)
Password requirements (minimum length, character groups that must exist) can be easily validated AND extended using look-aheads.
Submitted by OnlineCop - 8 years ago
1

Floating Point number verifier and extractor with scientific notation support

PCRE (PHP <7.3)
The regex verifies floating point numbers in decimal or scientific notation with extensive error checking - however, there may be edge cases which i haven't addressed, so feel free to put in more unit tests!
Submitted by Tamoghna Chowdhury - 8 years ago
1

RFC-1034- and RFC-2181-compliant FQDN extractor

PCRE (PHP <7.3)
The specification for this regex is based upon the extracts from RFC 1034 and RFC 2181 below. It is also assumed that you are trying to extract the FQDN from a pipe-delimited string. If this is not the case then you will need to adjust the regex as necessary by either removing the pipe character o...
Submitted by 0jag - 8 years ago
1

Extract the only the Nth field from a delimited string

PCRE (PHP <7.3)
The aim of this regex is to extract only the Nth field from a delimited string. In the example provided the delimited is the pipe character. You will have to substitute the pipe character for whatever delimiter you are using.
Submitted by 0jag - 8 years ago
1

Remove Markdown Links

PCRE (PHP <7.3)
no description available
Submitted by anonymous - 8 years ago
1

Make PHP var_dump() output more compact

PCRE (PHP <7.3)
The PHP function var_dump() provides debugging output, but has more line-breaks than is needed for readability. This regex strips out the (in my eyes) unnecessary line-breaks. Good in a self written debugging method in combination with ob_start()and ob_get_contents().
Submitted by Doqnach - 8 years ago
1

URL Slugs Optimized

PCRE (PHP <7.3)
This slug regex is optimized using strictly my own opinions. Slugs: Should be english, alphanumeric phrases separated with a single dash. Should not contain single alpha character between dashes. ...
Submitted by Jordon Baade - 8 years ago
1

A revised e-mail validation regular expression

PCRE (PHP <7.3)
This one allows to begin with a digit, however, sometimes e-mail should begin with an *English letter *
Submitted by anonymous - 8 years ago
1

Date checker for X values

ECMAScript (JavaScript)
Work in progress
Submitted by anonymous - 8 years ago
1

Youtube ID Extractor

PCRE (PHP <7.3)
no description available
Submitted by anonymous - 8 years ago
1

Telegram bot deep linking

PCRE (PHP <7.3)
Telegram bot deep linking Telegram bots have a deep linking mechanism, that allows for passing additional parameters to the bot on startup. It could be a command that launches the bot — or an auth token to connect the user's Telegram account to their account on some external service. ...
Submitted by SadeghPM@gmail.com - 8 years ago
1

Phone numbers and/or extensions(relaxed)

ECMAScript (JavaScript)
Useful for phone number extraction
Submitted by hslayer - 7 years ago
1

Localhost/private ip origin check

PCRE (PHP <7.3)
Used by CORS to check for localhost/private IP origins Check out the unit tests at /r/2Ofume/1/tests
Submitted by ngokimphu - 7 years ago
1

Formatar CPF

PCRE (PHP <7.3)
Retorna um cpf no formato 123.456.789-11. Cpf de entrada deve conter apenas números
Submitted by anonymous - 7 years ago
1

Matching email addresses per RFC5322

PCRE (PHP <7.3)
The BNF rules from RFC 5322 transformed to PCRE by Nikita Popov and described in the post http://nikic.github.io/2012/06/15/The-true-power-of-regular-expressions.html.
Submitted by Michael Musson - 7 years ago
1

Word Wrap examples

PCRE2 (PHP >=7.3)
Four examples of word wrapping at the 80 character mark, each one taking fewer steps than the last. Comment and uncomment lines with # to see the difference between versions. Optimization discussions welcome!
Submitted by OnlineCop - 7 years ago (Last modified a year ago)
1

Matching an Saudi Postal Code

PCRE (PHP <7.3)
Saudi Postal Code has five digits, if you would to have more information check the below: +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ First Digit (Postal Regions): "The postal region number is represented by the first digit of the postal code" ...
Submitted by Fares Alarabi - 7 years ago
1

Email matching with a grain of salt

PCRE (PHP <7.3)
Inspired by Micheal Musson entry Wich was hard to use in regex flavours that don't support recursion (C# engine doesn't) i've build my own simpler version wich matches what i would accept as validation entry
Submitted by Luigi Trabacchin - 7 years ago
1...760761762763764...902

Community Library Entry

1

Regular Expression
ECMAScript (JavaScript)

/
^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$
/
Open regex in editor

Description

Length of email address is an industry standard, lady "The format of email addresses is local-part@domain where the local part may be up to 64 characters long and the domain may have a maximum of 255 characters[2]—but the maximum of 256-character length of a forward or reverse path restricts the entire email address to be no more than 254 characters long.[3] The formal definitions are in RFC 5322 (sections 3.2.3 and 3.4.1) and RFC 5321—with a more readable form given in the informational RFC 3696[4] and the associated errata.

Link: https://en.wikipedia.org/wiki/Email_address#Syntax

Submitted by anonymous - 8 years ago