Properties¶

Class properties are variables, local to an object or a class.

They might have visibility, chosen among : public (default), protected and private.

They might have a default value. By default it is null.

They might have a type, since PHP 7.4

They might be readonly, for properties which are only set once, and cannot be modified.

They might be static, and not related to an object, but to a class.

Property should be uniquely defined in a class. They may be redefined in children or parent when the visibility allows it.

<?php

class X {
    private $property = 1;
}

?>

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