Undefined class readonly property in PhpStorm

Question

I'm using PhpStorm 2020.3 version and error undefined class 'readonly' property in PHP 8.1 new.

How to fix this error?

Answer 1

I used phpstorm 2020.3 version

You need to upgrade your PhpStorm.

The support for PHP 8.1 features has been added in PhpStorm 2021.3 version.

See "What’s New in PhpStorm 2021.3" on JetBrains website: https://www.jetbrains.com/phpstorm/whatsnew/2021-3/#php-81

Readonly properties

PhpStorm 2021.3 will help you make use of readonly properties in your code and make sure they are used correctly.