Regular Expression Functions (POSIX Extended)Regexps
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PHP also supports regular expressions using a Perl-compatible syntax
using the PCRE functions. Those functions
support non-greedy matching, assertions, conditional subpatterns, and a
number of other features not supported by the POSIX-extended regular
expression syntax.
These regular expression functions are not binary-safe. The PCRE functions are.
Regular expressions are used for complex string manipulation in
PHP. The functions that support regular expressions are:
eregereg_replaceeregieregi_replacesplitspliti
These functions all take a regular expression string as their
first argument. PHP uses the POSIX extended regular expressions
as defined by POSIX 1003.2. For a full description of POSIX
regular expressions see the regex man pages included in the regex
directory in the PHP distribution. It's in manpage format, so
you'll want to do something along the lines of man
/usr/local/src/regex/regex.7 in order to read it.
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&reference.regex.configure;
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Regular Expression Examples
tag at the beginning of $string.
$string = ereg_replace("^", " ", $string);
// Put a tag at the end of $string.
$string = ereg_replace("$", " ", $string);
// Get rid of any newline characters in $string.
$string = ereg_replace("\n", "", $string);
?>
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For regular expressions in Perl-compatible syntax have a look at the
PCRE functions. The simpler shell style
wildcard pattern matching is provided by fnmatch.
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