Search by regular expressions

Regular Expression

Purpose

Example

.

Match any single character (except a line break)

s.e matches "ste" in "step" and "sfe" in "transfer" but not "acro" in "across".

*

Match zero or more occurrences of the preceding expression (match as many characters as possible)

a*r matches "r" in "rack", "ar" in "ark", and "aar" in "aardvark"

.*

Match any character zero or more times (Wildcard *)

c.*e matches "cke" in "racket", "comme" in "comment", and "code" in "code"

+

Match one or more occurrences of the preceding expression (match as many characters as possible)

e.+e matches "eede" in "feeder" but not "ee".

.+

Match any character one or more times (Wildcard ?)

e.+e matches "eede" in "feeder" but not "ee".

*?

Match zero or more occurrences of the preceding expression (match as few characters as possible)

e.*?e matches "ee" in "feeder" but not "eede".

+?

Match one or more occurrences of the preceding expression (match as few characters as possible)

e.+?e matches "ente" and "erprise" in "enterprise", but not the whole word "enterprise".

^

Anchor the match string to the beginning of a line or string

^car matches the word "car" only when it appears at the beginning of a line.

\r?$

Anchor the match string to the end of a line

End\r?

[abc]

Match any single character in a set

b[abc] matches "ba", "bb", and "bc".

[a-f]

Match any character in a range of characters

be[n-t] matches "bet" in "between", "ben" in "beneath", and "bes" in "beside", but not "below".

()

Capture and implicitly number the expression contained within parenthesis

([a-z])X\1 matches "aXa"and "bXb", but not "aXb". ". "\1" refers to the first expression group "[a-z]".

(?!abc)

Invalidate a match

real (?!ity) matches "real" in "realty" and "really" but not in "reality." It also finds the second "real" (but not the first "real") in "realityreal".

[^abc]

Match any character that is not in a given set of characters

be[^n-t] matches "bef" in "before", "beh" in "behind", and "bel" in "below", but not "beneath".

|

Match either the expression before or the one after the symbol.

(sponge|mud)bath matches "spongebath" and "mudbath."

|\^

Escape the character following the backslash

{x},

Specify the number of occurrences of the preceding character or group

x(ab){2}x matches "xababx", and x(ab){2,3}xmatches "xababx" and "xabababx" but not "xababababx".

\p{X}

Match text in a Unicode character class, where "X" is the Unicode number.

\p{Lu} matches "T" and "D" in "Thomas Doe".

\b

Match a word boundary

\bin matches "in" in "inside" but not "pinto".

\r?\n

Match a line break (ie a carriage return followed by a new line).

End\r?\nBegin matches "End" and "Begin" only when "End" is the last string in a line and "Begin" is the first string in the next line.

\w

Match any alphanumeric character

a\wd matches "add" and "a1d" but not "a d".

(?[^\r\n])\s

Match any whitespace character.

Public\sInterface matches the phrase "Public Interface".

\d

Match any numeric character

\d matches and "3" in "3456", "2" in 23", and "1" in "1".

\uXXXX where XXXX specifies the Unicode character value

Match a Unicode character

\u0065 matches the character "e".

\b(\w+|[\w-[0-9\]]\w*)\b

Match an identifier

Matches "type1" but not &type1" or "#define".

((\".+?\")|('.+?'))

Match a string inside quotes

Matches any string inside single or double quotes.

\b0[xX]([0-9a-fA-F])\b

Match a hexadecimal number

Matches "0xc67f" but not "0xc67fc67f".

\b[0-9]\.\[0-9]+\b

Match integers and d

Matches "1.333".