PHP Manual: Check if strings are valid for the specified encoding

Description

bool mb_check_encoding(arraystringnull $value = null, stringnull $encoding = null)

Checks if the specified byte stream is valid for the specified encoding. If value is of type array, all keys and values are validated recursively. It is useful to prevent so-called "Invalid Encoding Attack".

Parameters

value: The byte stream or array to check. If it is omitted, this function checks all the input from the beginning of the request.

Warning
As of PHP 8.1.0, omitting this parameter or passing null is deprecated.
encoding: The expected encoding.

Return Values

Returns true on success or false on failure.

Changelog

Version	Description
8.1.0	Calling this function with `null` as `value` or without argument is deprecated.
8.0.0	`value` and `encoding` are nullable now.
7.2.0	This function now also accepts an array as `value`. Formerly, only strings have been supported.