C++ Regex Cheat Sheet

C++ Regex Cheat Sheet

AnchorsRegular Expressions Cheat Sheet
C++ Regex Cheat Sheet Download
C++ Regex Cheat Sheet 2019

Regex stands for the regular expression, and it is a technique to search string patterns from a string. It is used by many text editors such as Sublime, Notepad, Brackets, Microsoft word, etc for search and replaces operations. Regular Expression Cheat Sheet. Regular Expressions cheat sheet # javascript # beginners # tutorial # regex. Rae Liu Dec 3, 2020 ・2 min read. Regular expression is a powerful tool, and it can save. Regular expression tester with syntax highlighting, explanation, cheat sheet for PHP/PCRE, Python, GO, JavaScript, Java. Features a regex quiz & library. Regex101: build, test, and debug regex.
RegexPal also provides you with a larger list of regex examples as well as a regex cheat sheet for reference. If you're using regex in a web project and would like a quick reference to the regex tokens available, use the regex cheat sheet above as well the tools mentioned to help simplify the regex expression building process.
Anchros^
Start of string, or start of line in multi-line pattern
A
Start of string
$
End of string, or end of line in multi-line pattern
Z
End of string
b
Word boundary
B
Not word boundary
<
Start of word
>
End of word
QuantifiersQuantifiers*
0 or more
+
1 or more
?
0 or 1
{3}
Exactly 3
{3,}
3 or more
{3,5}
3, 4 or 5
{,5}
5 or less
CharacterCharacter Classesc
Control character
s
White space
S
Not white space
d
Digit
D
Not digit
w
Word
W
Not word
x
Hexade-cimal digit
O
Octal digit
Specialn
New line
r
Carriage return
t
Tab
v
Vertical tab
f
Form feed
xxx
Octal character xxx
xhh
Hex character hh
ExamplesMetacharacter^abc
abc, abcdefg, abc123, ...
abc$
abc, endsinabc, 123abc, ...
a.c
abc, aac, acc, adc, aec, ...
bill|ted
ted, bill
ab{2}c
abbc
a[bB]c
abc, aBc
(abc){2}
abcabc
ab*c
ac, abc, abbc, abbbc, ...
ab+c
abc, abbc, abbbc, ...
ab?c
ac, abc
asc
a c
Sample([A-Za-z0-9-]+)
Letters, numbers and hyphens
(d{1,2}/d{1,2}/d{4})
Date (e.g. 21/3/2006)
([^s]+(?=.(jpg|gif|png)).2)
jpg, gif or png image
(^[1-9]{1}$|^[1-4]{1}[0-9]{1}$|^50$)
Any number from 1 to 50 inclusive
(#?([A-Fa-f0-9]){3}(([A-Fa-f0-9]){3})?)
Valid hexadecimal colour code
((?=.*d)(?=.*[a-z])(?=.*[A-Z]).{8,15})
8 to 15 character string with at least one upper case letter, one lower case letter, and one digit (useful for passwords).
(w+@[a-zA-Z_]+?.[a-zA-Z]{2,6})
Email addresses
(<(/?[^>]+)>)
HTML Tag
Regular Expressions Cheat SheetPOSIXPOSIX[:upper:]
Upper case letters
[:lower:]
Lower case letters
[:alpha:]
All letters
[:alnum:]
Digits and letters
[:digit:]
Digits
[:xdigit:]
Hexade-cimal digits
[:punct:]
Punctu-ation
[:blank:]
Space and tab
[:space:]
Blank characters
[:cntrl:]
Control characters
[:graph:]
Printed characters
[:print:]
Printed characters and spaces
[:word:]
Digits, letters and underscore
GroupsGroups and Ranges.
Any character except new line (n)
(a|b)
a or b
(...)
Group
(?:...)
Passive (non-c-apt-uring) group
[abc]
Range (a or b or c)
[^abc]
Not a or b or c
[a-q]
Letter from a to q
[A-Q]
Upper case letter from A to Q
[0-7]
Digit from 0 to 7
n
nth group/-sub-pattern
ModifiersModifiersC++ Regex Cheat Sheet Downloadg
Global match
i
Case-i-nse-nsitive
m
Multiple lines
s
Treat string as single line
x
Allow comments and white space in pattern
e
Evaluate replac-ement
U
Ungreedy pattern
StringReplacement$n
nth non-pa-ssive group
$2
'-xyz-' in /^(abc-(xy-z))$/
$1
'-xyz-' in /^(?:a-bc)-(xyz)$/
$`
Before matched string
$'
After matched string
$+
Last matched string
$&
Entire matched string
C++ Regex Cheat Sheet 2019AssertionsAssertions?=
Lookahead assertion
?!
Negative lookahead
?<=
Lookbehind assertion
?!= or ?
Negative lookbehind
?>
Once-only Subexp-ression
?()
Condition [if then]
?()|
Condition [if then else]
?#
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