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Posted 17 Jun 2013

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Regex Quick Reference

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4.53 (14 votes)
25 Jun 2013CPOL
A convenient Regex overview.

Characters - single character of a certain type

\w

word character

\W

non-word character

\d

digit

\D

non-digit

\s

whitespace

\S

non-whitespace

\r

carriage return

\n

line feed

\t

tab

[\b]

backspace

\x00[1]

character by hex value

 

 

Quantifiers - specify number of times to match

?

zero or one

{n[2]}

n times

*

zero or more

{n[3],}

n or more times

+

one or more

{n[4], m}

n to m times

Ranges - specify a range of accepted values

[ abc ]

a,b, or c

[^ abc ]

not a,b, or c

[a-c]

a, c, or anything in between

a|c

either a or c

Anchors - specify a certain position to match

\b

word boundary

\B

not word boundary

\<

start of word

\>

end of word

^

start of line

$

end of line

Assertions - match a pattern without consuming

(?=pat[5])

positive look-ahead

(?!pat)

negative look-ahead

(?<=pat)

positive look-behind

(?<!pat)

negative look-behind

Groups - multiple characters grouped together

(pat)

group with back-reference

(?<name>pat)

group with named back-reference

\n[6]

refer to a back-referenced group

(?:pat)

group without back-reference

Modifiers - specify how the regex engine searches

(?i:pat)

case insensitive

(?-i:pat)

case sensitive

(?s:pat)

dot matches newline

(?-s:pat)

dot does not match newline

(?x:pat)

ignore pattern spacing

Index

  • [1] a specific character’s hexadecimal value
  • [2] an integer greater than 0
  • [3] an integer greater than or equal to 0
  • [4] an integer greater than or equal to 0
  • [5] a RegEx pattern
  • [6] the index of a group in a RegEx pattern
  • [7] the index of a group in a RegEx pattern

License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

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About the Author

FrostedSyntax
Web Developer JBHworks
United States United States
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Comments and Discussions

 
GeneralMy vote of 5 Pin
gramacha26-Jun-13 2:51
Membergramacha26-Jun-13 2:51 
Questiongud article Pin
harshal768926-Jun-13 1:48
Memberharshal768926-Jun-13 1:48 
QuestionAbout some example. Pin
csharpbd26-Jun-13 1:21
professionalcsharpbd26-Jun-13 1:21 
QuestionBetter documentation-2 Pin
Prasad Khandekar25-Jun-13 21:54
professionalPrasad Khandekar25-Jun-13 21:54 
QuestionA better documentation Pin
morgex25-Jun-13 21:24
Membermorgex25-Jun-13 21:24 

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