mb_ereg

(PHP 4 >= 4.2.0, PHP 5, PHP 7)

mb_ereg — Regular expression match with multibyte support

说明

mb_ereg ( string $pattern , string $string [, array &$regs ] ) : int

Executes the regular expression match with multibyte support.

参数

pattern

The search pattern.

string

The search string.

regs

If matches are found for parenthesized substrings of pattern and the function is called with the third argument regs, the matches will be stored in the elements of the array regs. If no matches are found, regs is set to an empty array.

$regs[1] will contain the substring which starts at the first left parenthesis; $regs[2] will contain the substring starting at the second, and so on. $regs[0] will contain a copy of the complete string matched.

返回值

Returns the byte length of the matched string if a match for pattern was found in string, or FALSE if no matches were found or an error occurred.

If the optional parameter regs was not passed or the length of the matched string is 0, this function returns 1.

更新日志

版本 说明
7.1.0 mb_ereg() will now set regs to an empty array, if nothing matched. Formerly, regs was not modified in that case.

注释

Note:

mb_regex_encoding() 指定的内部编码或字符编码将会当作此函数用的字符编码。

参见

  • mb_regex_encoding() - Set/Get character encoding for multibyte regex
  • mb_eregi() - Regular expression match ignoring case with multibyte support

User Contributed Notes

Anonymous 21-Mar-2019 08:24
<?php

// in PHP_VERSION 7.1

// WITHOUT $regs (3rd argument)
$int = mb_ereg('abcde', '_abcde_'); // [5 bytes match]
var_dump($int);                     // int(1)

$int = mb_ereg('ab', '_ab_');       // [2 bytes match]
var_dump($int);                     // int(1)

$int = mb_ereg('^', '_ab_');        // [0 bytes match]
var_dump($int);                     // int(1)

$int = mb_ereg('ab', '__');         // [not match]
var_dump($int);                     // bool(false)

$int = mb_ereg('', '_ab_');         // [error : empty pattern]
                                    // Warning: mb_ereg(): empty pattern in ...
var_dump($int);                     // bool(false)

$int = mb_ereg('ab');               // [error : fewer arguments]
                                    // Warning: mb_ereg() expects at least 2 parameters, 1 given in ...
var_dump($int);                     // bool(false)

                    // Without 3rd argument, mb_ereg() returns either int(1) or bool(false).

// WITH $regs (3rd argument)
$int = mb_ereg('abcde', '_abcde_', $regs);// [5 bytes match]
var_dump($int);                           // int(5)
var_dump($regs);                          // array(1) { [0]=> string(5) "abcde" }

$int = mb_ereg('ab', '_ab_', $regs);      // [2 bytes match]
var_dump($int);                           // int(2)
var_dump($regs);                          // array(1) { [0]=> string(2) "ab" }

$int = mb_ereg('^', '_ab_', $regs);       // [0 bytes match]
var_dump($int);                           // int(1)
var_dump($regs);                          // array(1) { [0]=> bool(false) }

$int = mb_ereg('ab', '__', $regs);        // [not match]
var_dump($int);                           // bool(false)
var_dump($regs);                          // array(0) { }

$int = mb_ereg('', '_ab_', $regs);        // [error : empty pattern]
                                          // Warning: mb_ereg(): empty pattern in ...
var_dump($int);                           // bool(false)
var_dump($regs);                          // array(0) { }

$int = mb_ereg('ab');                     // [error : fewer arguments]
                                          // Warning: mb_ereg() expects at least 2 parameters, 1 given in ...
var_dump($int);                           // bool(false)
var_dump($regs);                          // array(0) { }

                    // With 3rd argument, mb_ereg() returns either int(how many bytes matched) or bool(false)
                    // and 3rd argument is a bit complicated.

?>
lastuser at example dot com 14-Mar-2018 05:32
I hope this information is shown somewhere on php.net.

According to "https://github.com/php/php-src/tree/PHP-5.6/ext/mbstring/oniguruma",
the bundled Oniguruma regex library version seems ...
 4.7.1 between PHP 5.3 - 5.4.45,
 5.9.2 between PHP 5.5 - 7.1.16,
 6.3.0 since PHP 7.2 - .
Anonymous 11-Mar-2017 01:14
Old link to Oniguruma regex syntax is not working anymore, there is a working one:
https://github.com/geoffgarside/oniguruma/blob/master/Syntax.txt
mb_ereg() seems unable to Use &#34;named sub 06-May-2015 01:42
mb_ereg() seems unable to Use "named subpattern".
preg_match() seems a substitute only in UTF-8 encoding.

<?php

$text = 'multi_byte_string';
$pattern = '.*(?<name>string).*';        // "?P" causes "mbregex compile err" in PHP 5.3.5

if(mb_ereg($pattern, $text, $matches)){
    echo '<pre>'.print_r($matches, true).'</pre>';
}else{
    echo 'no match';
}

?>

This code ignores "?<name>" in $pattern and displays below.

Array
(
    [0] => multi_byte_string
    [1] => string
)

$pattern = '/.*(?<name>string).*/u';
if(preg_match($pattern, $text, $matches)){

instead of lines 2 & 3
displays below (in UTF-8 encoding).

Array
(
    [0] => multi_byte_string
    [name] => string
    [1] => string
)
Riikka K 13-Jul-2014 04:23
While hardly mentioned anywhere, it may be useful to note that mb_ereg uses Oniguruma library internally. The syntax for the default mode (ruby) is described here:

http://www.geocities.jp/kosako3/oniguruma/doc/RE.txt
pressler at hotmail dot de 19-Nov-2012 10:50
Note that mb_ereg() does not support the \uFFFF unicode syntax but uses \x{FFFF} instead:

<?PHP

$text = 'Peter is a boy.'; // english
$text = '???? ?? ???.'; // arabic
//$text = '???? ??? ???.'; // hebrew

mb_regex_encoding('UTF-8');

if(mb_ereg('[\x{0600}-\x{06FF}]', $text)) // arabic range
//if(mb_ereg('[\x{0590}-\x{05FF}]', $text)) // hebrew range
{
    echo "Text has some arabic/hebrew characters.";
}
else
{
    echo "Text doesnt have arabic/hebrew characters.";
}

?>
Jon 11-Apr-2009 04:22
Hebrew regex tested on PHP 5, Ubuntu 8.04.
Seems to work fine without the mb_regex_encoding lines (commented out).
Didn't seem to work with \uxxxx (also commented out).

<?php
echo "Line ";
//mb_regex_encoding("ISO-8859-8");
//if(mb_ereg(".*([\u05d0-\u05ea]).*", $this->current_line))
if(mb_ereg(".*([?-?]).*", $this->current_line))
{
    echo "has";
}
else
{
    echo "doesn't have";
}
echo " Hebrew characters.<br>";   
//mb_regex_encoding("UTF-8");
?>