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IntlChar::isblank	IntlChar::isdefined

IntlChar	Last updated: Mon, 26 Oct 2026

IntlChar::iscntrl

(PHP 7, PHP 8)

IntlChar::iscntrl — Check if code point is a control character

Description

public static function IntlChar::iscntrl(int|string $codepoint): ?bool

Determines whether the specified code point is a control character.

A control character is one of the following:

ISO 8-bit control character (U+0000..U+001f and U+007f..U+009f)
IntlChar::CHAR_CATEGORY_CONTROL_CHAR (Cc)
IntlChar::CHAR_CATEGORY_FORMAT_CHAR (Cf)
IntlChar::CHAR_CATEGORY_LINE_SEPARATOR (Zl)
IntlChar::CHAR_CATEGORY_PARAGRAPH_SEPARATOR (Zp)

Parameters

codepoint: The int codepoint value (e.g. 0x2603 for U+2603 SNOWMAN), or the character encoded as a UTF-8 string (e.g. "\u{2603}")

Return Values

Returns true if codepoint is a control character, false if not. Returns null on failure.

Examples

Example #1 Testing different code points

<?php
var_dump(IntlChar::iscntrl("A"));
var_dump(IntlChar::iscntrl(" "));
var_dump(IntlChar::iscntrl("\n"));
var_dump(IntlChar::iscntrl("\u{200e}"));
?>

The above example will output:

bool(false)
bool(false)
bool(true)
bool(true)

See Also

IntlChar::isprint() - Check if code point is a printable character
IntlChar::PROPERTY_DEFAULT_IGNORABLE_CODE_POINT
ctype_cntrl() - Check for control character(s)

IntlChar::isblank	IntlChar::isdefined

IntlChar	Last updated: Mon, 26 Oct 2026