Return part of a string

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- PHP Manual
- Grapheme Functions
- Return part of a string

# grapheme_substr

(PHP 5 >= 5.3.0, PHP 7, PHP 8, PECL intl >= 1.0.0)

grapheme_substr — Return part of a string

### Description

Procedural style

grapheme_substr(string `$string`, int `$offset`, ?int `$length` = `null`): string|false

Return part of a string

### Parameters

`string`

  The input string. Must be valid UTF-8.

`offset`

  Start position in default grapheme units. If `offset` is non-negative, the returned string will start at the `offset`'th position in `string`, counting from zero. If `offset` is negative, the returned string will start at the `offset`'th grapheme unit from the end of string.

`length`

  Length in grapheme units. If `length` is given and is positive, the string returned will contain at most `length` grapheme units beginning from `offset` (depending on the length of string). If `length` is given and is negative, then that many grapheme units will be omitted from the end of string (after the start position has been calculated when `offset` is negative). If `offset` denotes a position beyond this truncation, an empty string will be returned.

### Return Values

Returns the extracted part of `string`, or `false` on failure.

### Changelog

Version | Description
--- | ---
8.0.0 | The function now consistently clamps out-of-bounds offsets to the string boundary. Previously, `false` was returned instead of the empty string in some cases.

### Examples

Example #1 grapheme_substr() example

    <?php

    $char_a_ring_nfd = "a\xCC\x8A";  // 'LATIN SMALL LETTER A WITH RING ABOVE' (U+00E5) normalization form "D"
    $char_o_diaeresis_nfd = "o\xCC\x88"; // 'LATIN SMALL LETTER O WITH DIAERESIS' (U+00F6) normalization form "D"

    print urlencode(grapheme_substr( "ao" . $char_a_ring_nfd . "bc" . $char_o_diaeresis_nfd . "O", 2, -1 ));
    ?>

The above example will output:

    a%CC%8Abco%CC%88

### See Also

- grapheme_extract() - Function to extract a sequence of default grapheme clusters from a text buffer, which must be encoded in UTF-8
- » Unicode Text Segmentation: Grapheme Cluster Boundaries