Webmaster in a Nutshell, Second Edition

Regular Expressions

JavaScript 1.2 supports regular expressions, using the same syntax as Perl 4. A regular expression is specified literally as a sequence of characters within forward slashes (/), or as a JavaScript string passed to the RegExp() constructor. The optional g (global search) and i (case-insensitive search) modifiers may follow the second / character, or may be passed to RegExp().

The following table summarizes regular expression syntax:

Character	Meaning
\n, \r, \t	Match literal newline, carriage return, tab
\, \/, \*, \+, \?, etc.	Match a special character literally, ignoring or escaping its special meaning
[ . . . ]	Match any one character between brackets
[^ . . . ]	Match any one character not between brackets
.	Match any character other than newline
\w, \W	Match any word/nonword character
\s, \S	Match any whitespace/nonwhitespace
\d, \D	Match any digit/nondigit
^, $	Require match at beginning/end of a string, or in multiline mode, beginning/end of a line
\b, \B	Require match at a word boundary nonboundary
?	Optional term; match zero or one time
+	Match previous term one or more times
*	Match term zero or more times
{ n }	Match previous term exactly n times
{ n,}	Match previous term n or more times
{ n,m }	Match at least n but no more than m times
a | b	Match either a or b
( sub )	Group subexpression sub into a single term, and remember the text that it matched
n	Match exactly the same characters that were matched by subexpression ...