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    mb_strpos

    (PHP 4 >= 4.0.6, PHP 5, PHP 7, PHP 8)

    mb_strpos — Find position of first occurrence of string in a string

    Description

    mb_strpos(
        string $haystack,
        string $needle,
        int $offset = 0,
        ?string $encoding = null
    ): int|false

    Finds position of the first occurrence of a string in a string.

    Performs a multi-byte safe strpos() operation based on number of characters. The first character's position is 0, the second character position is 1, and so on.

    Parameters

    haystack

    The string being checked.

    needle

    The string to find in haystack. In contrast with strpos(), numeric values are not applied as the ordinal value of a character.

    offset

    The search offset. If it is not specified, 0 is used. A negative offset counts from the end of the string.

    encoding

    The encoding parameter is the character encoding. If it is omitted or null, the internal character encoding value will be used.

    Return Values

    Returns the numeric position of the first occurrence of needle in the haystack string. If needle is not found, it returns false.

    Changelog

    Version Description
    8.0.0 needle now accepts an empty string.
    8.0.0 encoding is nullable now.
    7.1.0 Support for negative offsets has been added.

    See Also

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    User Contributed Notes 3 notes

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    3
    stestagg at talk21 dot com
    18 years ago
    It appears that the $offset value is a character count not a byte count.  (This may seem obvious but it isn't explicitly stated)
    up
    -3
    stestagg at talk21 dot com
    18 years ago
    a sample mb_str_replace function:

    function mb_str_replace($haystack, $search,$replace, $offset=0,$encoding='auto'){
        $len_sch=mb_strlen($search,$encoding);
        $len_rep=mb_strlen($replace,$encoding);
       
        while (($offset=mb_strpos($haystack,$search,$offset,$encoding))!==false){
            $haystack=mb_substr($haystack,0,$offset,$encoding)
                .$replace
                .mb_substr($haystack,$offset+$len_sch,1000,$encoding);
            $offset=$offset+$len_rep;
            if ($offset>mb_strlen($haystack,$encoding))break;
        }
        return $haystack;
    }
    up
    -19
    stestagg at talk21 dot com
    18 years ago
    sorry, my previous post had an error.  replace the 1000 with strlen($haystack) to handle strings longer than 1000 chars.

    btw. This is an issue with the mbstring functions.  you can't specify the $encoding without specifying a $length, thus this reduces the functionality of mb_substr compared to substr
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