PHP マニュアル: Check whether a locale uses a right-to-left writing system

public static bool Locale::isRightToLeft( string $locale = "" )

Determines whether a locale uses a right-to-left writing system.

This method relies on the ICU library and evaluates the dominant script associated with the locale.

If an empty string is provided, the default locale is used.

Returns true if the locale uses a right-to-left writing system, or false otherwise.

バージョン	説明
8.5.0	Added Locale::isRightToLeft.

例1 Checking text direction for a locale

var_dump(Locale::isRightToLeft('en-US'));
var_dump(Locale::isRightToLeft('ar'));

上の例の出力は以下となります。

bool(false)
bool(true)