php面向對象和面向過程的區別，PHP 中的對象傳遞

<?php
class A
{public $age = 0;public $username = "";public $obj = null;
}$a = new A();
$b = $a;$b->age = 1;var_dump($b);
var_dump($a);debug_zval_dump($a);
echo "<br/>";
debug_zval_dump($b);

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