Class Constants

Class constants store values that should not change.

They are defined using the const keyword.

Example

class Config {
const APP_NAME = "My Application";
const VERSION = "1.0";
}

echo Config::APP_NAME;

Access inside class

class MathHelper {
const PI = 3.14159;

    public function area($radius) {
        return self::PI * $radius * $radius;
    }

}