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Regular Expressions

24. Pattern Reference

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We'll finish this series of tutorials on regular expressions with a list of all of the different special character combinations that can be used in regular expressions. The links back to the tutorials that discuss those patterns will allow you to use this reference as an index to the tutorials.

If you are familiar with regular expressions in some other language (eg. PERL or PHP) then you may notice that some of the constructs available in those languages are not listed here. This is because Javascript does not support some of the more advanced regular expression constructs such as intersecting groups.

^ beginning of string or line
$ end of string or line
\/ a single slash character
\\ a single slosh (backslash) character
A|B either A or B
[AFH] any one of the enclosed characters
[^AFH] any character except one of the enclosed characters
[A-Z] any letter within the specified range
[0-9] any number within the specified range
\[ a single open bracket character
\] a single close bracket character
T{n} exactly "n" occurrences of the previous character or group
T{n,} "n" or more occurrences of the previous character or group
T{n,m} at least "n" and not more than "m" occurrences of the previous character or group
T? zero or one of the previous character or group
T* zero or more of the previous character or group (match the longest string)
T+ one or more of the previous character or group match the longest string)
T*? zero or more of the previous character or group (match the shortest string)
T+? one or more of the previous character or group match the shortest string)
\d any number
\D anything except a number
\w any number, letter, or underscore
\W anything except a number, letter, or underscore
\s any whitespace (spaces, tabs, linefeeds, carriage returns, and nulls)
\S anything except whitespace
. anything except a linefeed or carriage return
\t a tab
\n a new line character
\r a carriage return
\f a form feed
\v a vertical tab
\0 the null character
\a an alert
\e escape key
\cX control-X
\x99 ASCII character 99 (hexadecimal)
\o999 ASCII character 999 (octal)
\u9999 Unicode character 9999 (hexadecimal)
\b start or end of word (word boundary)
[\b] backspace
(AFH) these characters form a capturing group
(?:AFH) these characters form a non-capturing group
(?=AFH) lookahead for equal to this non-capturing group
(?!AFH) lookahead for not equal to this non-capturing group

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