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Regular Expression Functions (POSIX Extended)

Introducere

Sfat

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.

Avertizare

These regular expression functions are not binary-safe. The PCRE functions are.

Regular expressions are used for complex string manipulation. 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.

Necesităţi

Nu sunt necesare biblioteci externe pentru a asambla această extensie.

Instalarea

Avertizare

Do not change the TYPE unless you know what you are doing.

To enable regexp support configure PHP --with-regex[=TYPE]. TYPE can be one of system, apache, php. The default is to use php.

Versiunea PHP pentru Windows susţine implicit această extensie. Nu este nevoie să încărcaţi vre-o extensie suplimentară pentru a putea utiliza aceste funcţii.

Configuraţia la rulare

Această extensie nu are directive de configurare definite în php.ini.

Tipurile resurselor

Această extensie nu are tipuri de resurse definite.

Constante predefinite

Această extensie nu are constante definite.

Exemple

Example#1 Regular Expression Examples

<?php
// Returns true if "abc" is found anywhere in $string.
ereg("abc"$string);            

// Returns true if "abc" is found at the beginning of $string.
ereg("^abc"$string);

// Returns true if "abc" is found at the end of $string.
ereg("abc$"$string);

// Returns true if client browser is Netscape 2, 3 or MSIE 3.
eregi("(ozilla.[23]|MSIE.3)"$_SERVER["HTTP_USER_AGENT"]);

// Places three space separated words into $regs[1], $regs[2] and $regs[3].
ereg("([[:alnum:]]+) ([[:alnum:]]+) ([[:alnum:]]+)"$string$regs); 

// Put a <br /> tag at the beginning of $string.
$string // Put a <br /> tag at the beginning of $string.
$string ereg_replace("^""<br />"$string); 
 
// Put a <br /> tag at the end of $string.
$string ereg_replace("$""<br />"$string); 

// Get rid of any newline characters in $string.
$string ereg_replace("\n"""$string);
?>

Vedeţi de asemenea

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().

Cuprins

  • ereg_replace — Replace regular expression
  • ereg — Regular expression match
  • eregi_replace — Replace regular expression case insensitive
  • eregi — Case insensitive regular expression match
  • split — Split string into array by regular expression
  • spliti — Split string into array by regular expression case insensitive
  • sql_regcase — Make regular expression for case insensitive match