将 stdClass 对象转换/强制转换为另一个类

See the manual on Type Juggling on possible casts.

The casts allowed are:

• (int), (integer) - cast to integer
• (bool), (boolean) - cast to boolean
• (float), (double), (real) - cast to float
• (string) - cast to string
• (array) - cast to array
• (object) - cast to object
• (unset) - cast to NULL (PHP 5)

You would have to write a Mapper that does the casting from stdClass to another concrete class. Shouldn't be too hard to do.

Or, if you are in a hackish mood, you could adapt the following code:

function arrayToObject(array $array, $className) {
return unserialize(sprintf(
'O:%d:"%s"%s',
strlen($className),
$className,
strstr(serialize($array), ':')
));
}

which pseudocasts an array to an object of a certain class. This works by first serializing the array and then changing the serialized data so that it represents a certain class. The result is unserialized to an instance of this class then. But like I said, it's hackish, so expect side-effects.

For object to object, the code would be

function objectToObject($instance, $className) {
return unserialize(sprintf(
'O:%d:"%s"%s',
strlen($className),
$className,
strstr(strstr(serialize($instance), '"'), ':')
));
}

To move all existing properties of a stdClass to a new object of a specified class name:

/**
* recast stdClass object to an object with type
*
* @param string $className
* @param stdClass $object
* @throws InvalidArgumentException
* @return mixed new, typed object
*/
function recast($className, stdClass &$object)
{
if (!class_exists($className))
throw new InvalidArgumentException(sprintf('Inexistant class %s.', $className));


$new = new $className();


foreach($object as $property => &$value)
{
$new->$property = &$value;
unset($object->$property);
}
unset($value);
$object = (unset) $object;
return $new;
}

Usage:

$array = array('h','n');


$obj=new stdClass;
$obj->action='auth';
$obj->params= &$array;
$obj->authKey=md5('i');


class RestQuery{
public $action;
public $params=array();
public $authKey='';
}


$restQuery = recast('RestQuery', $obj);


var_dump($restQuery, $obj);

Output:

object(RestQuery)#2 (3) {
["action"]=>
string(4) "auth"
["params"]=>
&array(2) {
[0]=>
string(1) "h"
[1]=>
string(1) "n"
}
["authKey"]=>
string(32) "865c0c0b4ab0e063e5caa3387c1a8741"
}
NULL

This is limited because of the new operator as it is unknown which parameters it would need. For your case probably fitting.

You can use above function for casting not similar class objects (PHP >= 5.3)

/**
* Class casting
*
* @param string|object $destination
* @param object $sourceObject
* @return object
*/
function cast($destination, $sourceObject)
{
if (is_string($destination)) {
$destination = new $destination();
}
$sourceReflection = new ReflectionObject($sourceObject);
$destinationReflection = new ReflectionObject($destination);
$sourceProperties = $sourceReflection->getProperties();
foreach ($sourceProperties as $sourceProperty) {
$sourceProperty->setAccessible(true);
$name = $sourceProperty->getName();
$value = $sourceProperty->getValue($sourceObject);
if ($destinationReflection->hasProperty($name)) {
$propDest = $destinationReflection->getProperty($name);
$propDest->setAccessible(true);
$propDest->setValue($destination,$value);
} else {
$destination->$name = $value;
}
}
return $destination;
}

EXAMPLE:

class A
{
private $_x;
}


class B
{
public $_x;
}


$a = new A();
$b = new B();


$x = cast('A',$b);
$x = cast('B',$a);

I have a very similar problem. Simplified reflection solution worked just fine for me:

public static function cast($destination, \stdClass $source)
{
$sourceReflection = new \ReflectionObject($source);
$sourceProperties = $sourceReflection->getProperties();
foreach ($sourceProperties as $sourceProperty) {
$name = $sourceProperty->getName();
$destination->{$name} = $source->$name;
}
return $destination;
}

Changed function for deep casting (using recursion)

/**
* Translates type
* @param $destination Object destination
* @param stdClass $source Source
*/
private static function Cast(&$destination, stdClass $source)
{
$sourceReflection = new \ReflectionObject($source);
$sourceProperties = $sourceReflection->getProperties();
foreach ($sourceProperties as $sourceProperty) {
$name = $sourceProperty->getName();
if (gettype($destination->{$name}) == "object") {
self::Cast($destination->{$name}, $source->$name);
} else {
$destination->{$name} = $source->$name;
}
}
}

Hope that somebody find this useful

// new instance of stdClass Object
$item = (object) array(
'id'     => 1,
'value'  => 'test object',
);


// cast the stdClass Object to another type by passing
// the value through constructor
$casted = new ModelFoo($item);


// OR..


// cast the stdObject using the method
$casted = new ModelFoo;
$casted->cast($item);

class Castable
{
public function __construct($object = null)
{
$this->cast($object);
}


public function cast($object)
{
if (is_array($object) || is_object($object)) {
foreach ($object as $key => $value) {
$this->$key = $value;
}
}
}
}

class ModelFoo extends Castable
{
public $id;
public $value;
}

BTW: Converting is highly important if you are serialized, mainly because the de-serialization breaks the type of objects and turns into stdclass, including DateTime objects.

I updated the example of @Jadrovski, now it allows objects and arrays.

example

$stdobj=new StdClass();
$stdobj->field=20;
$obj=new SomeClass();
fixCast($obj,$stdobj);

example array

$stdobjArr=array(new StdClass(),new StdClass());
$obj=array();
$obj[0]=new SomeClass(); // at least the first object should indicates the right class.
fixCast($obj,$stdobj);

code: (its recursive). However, i don't know if its recursive with arrays. May be its missing an extra is_array

public static function fixCast(&$destination,$source)
{
if (is_array($source)) {
$getClass=get_class($destination[0]);
$array=array();
foreach($source as $sourceItem) {
$obj = new $getClass();
fixCast($obj,$sourceItem);
$array[]=$obj;
}
$destination=$array;
} else {
$sourceReflection = new \ReflectionObject($source);
$sourceProperties = $sourceReflection->getProperties();
foreach ($sourceProperties as $sourceProperty) {
$name = $sourceProperty->getName();
if (is_object(@$destination->{$name})) {
fixCast($destination->{$name}, $source->$name);
} else {
$destination->{$name} = $source->$name;
}
}
}
}

consider adding a new method to BusinessClass:

public static function fromStdClass(\stdClass $in): BusinessClass
{
$out                   = new self();
$reflection_object     = new \ReflectionObject($in);
$reflection_properties = $reflection_object->getProperties();
foreach ($reflection_properties as $reflection_property)
{
$name = $reflection_property->getName();
if (property_exists('BusinessClass', $name))
{
$out->{$name} = $in->$name;
}
}
return $out;
}

then you can make a new BusinessClass from $stdClass:

$converted = BusinessClass::fromStdClass($stdClass);

Yet another approach.

The following is now possible thanks to the recent PHP 7 version.

$theStdClass = (object) [
'a' => 'Alpha',
'b' => 'Bravo',
'c' => 'Charlie',
'd' => 'Delta',
];


$foo = new class($theStdClass)  {
public function __construct($data) {
if (!is_array($data)) {
$data = (array) $data;
}


foreach ($data as $prop => $value) {
$this->{$prop} = $value;
}
}
public function word4Letter($letter) {
return $this->{$letter};
}
};


print $foo->word4Letter('a') . PHP_EOL; // Alpha
print $foo->word4Letter('b') . PHP_EOL; // Bravo
print $foo->word4Letter('c') . PHP_EOL; // Charlie
print $foo->word4Letter('d') . PHP_EOL; // Delta
print $foo->word4Letter('e') . PHP_EOL; // PHP Notice:  Undefined property

In this example, $foo is being initialized as an anonymous class that takes one array or stdClass as only parameter for the constructor.

Eventually, we loop through the each items contained in the passed object and dynamically assign then to an object's property.

To make this approch event more generic, you can write an interface or a Trait that you will implement in any class where you want to be able to cast an stdClass.

And yet another approach using the decorator pattern and PHPs magic getter & setters:

// A simple StdClass object
$stdclass = new StdClass();
$stdclass->foo = 'bar';


// Decorator base class to inherit from
class Decorator {


protected $object = NULL;


public function __construct($object)
{
$this->object = $object;
}


public function __get($property_name)
{
return $this->object->$property_name;
}


public function __set($property_name, $value)
{
$this->object->$property_name = $value;
}
}


class MyClass extends Decorator {}


$myclass = new MyClass($stdclass)


// Use the decorated object in any type-hinted function/method
function test(MyClass $object) {
echo $object->foo . '<br>';
$object->foo = 'baz';
echo $object->foo;
}


test($myclass);

Convert it to an array, return the first element of that array, and set the return param to that class. Now you should get the autocomplete for that class as it will regconize it as that class instead of stdclass.

/**
* @return Order
*/
public function test(){
$db = new Database();


$order = array();
$result = $db->getConnection()->query("select * from `order` where productId in (select id from product where name = 'RTX 2070')");
$data = $result->fetch_object("Order"); //returns stdClass
array_push($order, $data);


$db->close();
return $order[0];
}