Advanced Features for PHP classes and object 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 = = $b) echo ' = = ';   Trueif ($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); The object is serialized into a string echo $str. ' <br> '; $b = Unserialize ($STR); Deserializes to Object Var_dump ($b);

Advanced Features for PHP classes and object objects