Advanced Features of PHP objects

Object comparison , when all the properties of two instances of the same class are equal, you can use the comparison operator = = To determine whether a two variable is a reference to the same object, you can use the congruent operator = = =.

Class Car {

}

$a = new Car ();

$b = new Car ();

if ($a = = $b) echo ' = = '; True

if ($a = = = $b) echo ' = = = '; False

object replication , in some special cases, you can copy an object by using the keyword clone, at which point the __clone method is called, and the value of the property is set by this magic method.

Class Car {

Public $name = ' car ';

Public Function __clone () {

$obj = new Car ();

$obj->name = $this->name;

}

}

$a = new Car ();

$a->name = ' new car ';

$b = Clone $a;

Var_dump ($b);

object serialization , which can be serialized as a string by the Serialize method, used to store or pass data, and then deserialize the string into an object when needed by Unserialize.

Class Car {

Public $name = ' car ';

}

$a = new Car ();

$str = serialize ($a); object is serialized into a string

echo $str. ' <br> ';

$b = Unserialize ($STR); Deserializing objects

Var_dump ($b);

Advanced Features of PHP objects