isset(), empty() And the Magic Methods¶

<?php

class x {
    private array $config = array();

    function __isset($name) {
            print __METHOD__." ".$name.PHP_EOL;
        return isset($this->config[$name]);
    }

        function __get($name) {
            print __METHOD__." ".$name.PHP_EOL;
            return 'a';
    }

}


$x = new x;
var_dump(isset($x->a));
var_dump(empty($x->a));

The __isset() and __get() methods must go hand in hand. One checks that a property, virtual or not, is available, and the other one returns the actual value. Yet, both may be inconsistent one with the other.

In particular, __isset() is called when dealing with isset() and empty().

But __get() may be called directly, and return something, even if __isset() is saying it’s not set.

This might come as a surprise to pieces of code that compare a property with == '' (or equivalent), compared to using isset().

Beyond the strange illustration, it is probably a good practice to always provide __isset() on a class that has the magic method __get.

PHP Features¶

Last updated: 14 July 2026

isset(), empty() And the Magic Methods¶

See Also¶

PHP Features¶