Regular Expressions 101

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Community Patterns

1

Match any line that starts with '[' and ends with ']'

PCRE (PHP <7.3)
Match any line that starts with '[' and ends with ']'
Submitted by anonymous - 8 years ago
1

Find particular punctuation

ECMAScript (JavaScript)
This regex find punctuation like "!", "!!!", "?", "???", "!?", "!!!???" and unlimited time repeated "!" and "?"
Submitted by Ivijan-Stefan Stipic - 8 years ago
1

Match Time in either 24Hr or 12Hr format

PCRE (PHP <7.3)
Matches a time in either 25Hr or 12Hr format. Seconds are optional for either format.
Submitted by anonymous - 8 years ago
1

Version number validation

PCRE (PHP <7.3)
E.g. android version name or ios bundle id validation
Submitted by Paldom - 8 years ago
1

dick detector

PCRE (PHP <7.3)
detect 8=D regex
Submitted by anonymous - 8 years ago
1

RFC 3986 IPv4 Validation

PCRE (PHP <7.3)
IPv4 Validation to RFC 3986 found at https://tools.ietf.org/html/rfc3986#section-1.1.1.
Submitted by anonymous - 8 years ago
1

Android package name

PCRE (PHP <7.3)
Validation of android package names. Read more
Submitted by Paldom - 8 years ago
1

Domain validation regex suitable for user input

Golang
This regexp can be used to validate domain names in Golang. While it cannot enforce the 253 character limit (with optional trailing period not included) that can be easily done by a simple len(domain) <= 253 check as well. This can be used as-is in other languages, even with RE2 regex engine. If po...
Submitted by Alexander Dupuy - 5 years ago
1

Return XML tag where attribute value equals X

PCRE (PHP <7.3)
Return XML tag where attribute value equals X
Submitted by anonymous - 8 years ago
1

Get the name of the image

PCRE (PHP <7.3)
This regex will be getting the name of the image source: data/products/cocacola/logo_new_version.jpg match: logo_new_version It will be returned logo_new_version on image index...
Submitted by strubloid - 8 years ago
1

Regrex email wiki

ECMAScript (JavaScript)
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 ent...
Submitted by anonymous - 8 years ago
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...274275276277278...902

Community Library Entry

1

Regular Expression
PCRE (PHP <7.3)

/
^(?![0-9-]+$)(?:[a-z]{2,}-?|[0-9]-?)+(?<!-)$
/
gm
Open regex in editor

Description

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. Should not be comprised of just numbers and dashes. Should not begin with a number or a dash. Should not end with a dash.

2+ alpha character lookup increases expression speed greatly over allowing 1+ alpha lookups, 3+ improves it more although marginally.)

Submitted by Jordon Baade - 8 years ago