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    mb_ereg

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

    mb_ereg — Regular expression match with multibyte support

    Description

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

    Executes the regular expression match with multibyte support.

    Parameters

    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.

    Return Values

    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.

    Changelog

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

    Notes

    Note:

    The internal encoding or the character encoding specified by mb_regex_encoding() will be used as the character encoding for this function.

    See Also

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

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    User Contributed Notes 7 notes

    up
    4
    Anonymous
    1 year ago
    Old link to Oniguruma regex syntax is not working anymore, there is a working one:
    https://github.com/geoffgarside/oniguruma/blob/master/Syntax.txt
    up
    2
    pressler at hotmail dot de
    6 years ago
    Note that mb_ereg() does not support the \uFFFF unicode syntax but uses \x{FFFF} instead:

    <?PHP

    $text     = 'Peter is a boy.'; // english
    $text = 'بيتر هو صبي.'; // arabic
    //$text = 'פיטר הוא ילד.'; // 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.";
    }

    ?>
    up
    0
    lastuser at example dot com
    8 months ago
    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 - .
    up
    0
    mb_ereg() seems unable to Use &#34;named sub
    3 years ago
    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
    )
    up
    0
    Riikka K
    4 years ago
    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
    up
    -1
    Never Do This !
    10 months ago
    Do Not Identically compare (===/!==) "TRUE" with return value of mb_ereg().
    eg
    <?php
    // This doesn't work.
    if (mb_ereg('bad', 'bad_input') === true) {
    // (or) if (mb_ereg('good', 'good_input') !== true) {
            die('Get out of here !');
    }else{
        echo     'safe';   // continue processing...
    }
    ?>

    // These work. (not using TRUE)
    if (mb_ereg('bad', 'bad_input')) {.....
    if (!mb_ereg('good', 'good_input')) {.....

    mb_ereg() never returns TRUE, but False (in unmatch case) or Integer (in match case, >=1, which equals TRUE).
    up
    -1
    Jon
    9 years ago
    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(".*([א-ת]).*", $this->current_line))
    {
        echo     "has";
    }
    else
    {
        echo     "doesn't have";
    }
    echo     " Hebrew characters.<br>";   
    //mb_regex_encoding("UTF-8");
    ?>
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