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

Descrizione

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.

Elenco dei parametri

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: Il parametro encoding è la codifica dei caratteri. Se è omesso, verrà utilizzata la codifica interna.

Valori restituiti

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

Log delle modifiche

Versione	Descrizione
8.0.0	`needle` now accepts an empty string.
8.0.0	`encoding` is nullable now.
7.1.0	Support for negative `offset`s has been added.

Vedere anche:

mb_internal_encoding() - Set/Get internal character encoding
strpos() - Trova la posizione della prima occorrenza di una stringa

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User Contributed Notes 3 notes

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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)

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-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;
}

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-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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