README

Version 1.2.0

Copyright © 2015-2026 Martijn van der Lee. MIT Open Source license applies.

Introduction

A collection of multibyte string helpers and compatibility polyfills. Functions are only declared when PHP does not already provide them, so the package can be loaded safely on both legacy and current PHP releases.

Release 1.2.0

Version 1.2.0 adds PHP 8.4-compatible guarded polyfills, common multibyte string helpers, and support for current PHP releases without dropping the legacy PHP 5.x-compatible syntax.

Highlights:

• Safe loading on PHP 8.4 and newer without native-function redeclaration.
• New mb_trim(), mb_ltrim(), mb_rtrim(), mb_ucfirst(), and mb_lcfirst() compatibility implementations.
• New mb_str_split() and mb_str_pad() polyfills.
• New mb_strrev(), mb_substr_replace(), and mb_chunk_split() helpers.
• Automated testing across PHP 5.3, 5.6, 7.4, 8.3, 8.4, and 8.5.

PHP compatibility polyfills

• mb_trim($string, $characters = null, $encoding = null)
• mb_ltrim($string, $characters = null, $encoding = null)
• mb_rtrim($string, $characters = null, $encoding = null)
• mb_ucfirst($string, $encoding = null)
• mb_lcfirst($string, $encoding = null)
• mb_str_split($string, $length = 1, $encoding = null)
• mb_str_pad($string, $length, $padString = ' ', $padType = STR_PAD_RIGHT, $encoding = null)

The trim functions use PHP 8.4's Unicode whitespace set when $characters is null. Explicit trim characters are treated as a simple list; range notation such as a..z is not supported, matching the native API.

Additional string helpers

mb_explode

array mb_explode($pattern, $subject[, $limit = -1[, $flags = 0 ] ])

Multibyte version of preg_split, including its flags. The $pattern behaves like an mb_split pattern; the other arguments and return value follow preg_split.

mb_ucwords

string mb_ucwords($string[, string $encoding = mb_internal_encoding() ])

Uppercase the first character of each whitespace-delimited word in a string.

mb_strrev

string mb_strrev($string[, string $encoding = mb_internal_encoding() ])

Reverse a string by characters instead of bytes.

mb_substr_replace

string mb_substr_replace($string, $replacement, $start[, $length = null[, $encoding = null ]])

Replace a character range within a multibyte string, including support for negative offsets and lengths.

mb_chunk_split

string mb_chunk_split($string[, $length = 76[, $separator = "\r\n"[, $encoding = null ]]])

Split a string into fixed-width character chunks and append a separator to each chunk.

Installation

composer require vanderlee/multibyte

Development

composer install
composer test