Ive got this snippet of code below which works perfectly fine. I have been profiling it and the bit of code gets used alot of times, so I want to try figure out how to write it in a way that will perform better than the current way its written.
Is there a more efficient way to write this?
function objectToArray($d) {
if (is_object($d)) {
// Gets the properties of the given object
// with get_object_vars function
$d = get_object_vars($d);
}
if (is_array($d)) {
// Return array converted to object Using __FUNCTION__ (Magic constant) for recursive call
return array_map(__FUNCTION__, $d);
}
else {
// Return array
return $d;
}
}
You could implement a toArray() method to the class that needs to be converted:
e.g.
class foo
{
protected $property1;
protected $property2;
public function __toArray()
{
return array(
'property1' => $this->property1,
'property2' => $this->property2
);
}
}
Having access to the protected properties and having the whole conversion encapsulated in the class is in my opinion the best way.
Update
One thing to note is that the get_object_vars() function will only return the publically accessible properties - Probably not what you are after.
If the above is too manual of a task the accurate way from outside the class would be to use PHP (SPL) built in ReflectionClass:
$values = array();
$reflectionClass = new \ReflectionClass($object);
foreach($reflectionClass->getProperties() as $property) {
$values[$property->getName()] = $property->getValue($object);
}
var_dump($values);
depends what kind of object it is, many standard php objects have methods built in to convert them
for example MySQLi results can be converted like this
$resultArray = $result->fetch_array(MYSQLI_ASSOC);
if its a custom class object you might consider implementing a method in that class for that purpose as AlexP sugested
Ended up going with:
function objectToArray($d) {
$d = (object) $d;
return $d;
}
function arrayToObject($d) {
$d = (array) $d;
return $d;
}
As AlexP said you can implement a method __toArray(). Alternatively to ReflexionClass (which is complex and expensive), making use of object iteration properties, you can iterate $this as follow
class Foo
{
protected $var1;
protected $var2;
public function __toArray()
{
$result = array();
foreach ($this as $key => $value) {
$result[$key] = $value;
}
return $result;
}
}
This will also iterate object attributes not defined in the class: E.g.
$foo = new Foo;
$foo->var3 = 'asdf';
var_dump($foo->__toArray());)
See example http://3v4l.org/OnVkf
This is the fastest way I have found to convert object to array. Works with Capsule as well.
function objectToArray ($object) {
return json_decode(json_encode($object, JSON_FORCE_OBJECT), true);
}
Related
I'm trying to JSON encode some objects in PHP, but I'm facing a problem: I want to encode data which is kept by a class private members.
I found this piece of code to encode this object by calling an encode function like:
public function encodeJSON()
{
foreach ($this as $key => $value)
{
$json->$key = $value;
}
return json_encode($json);
}
However, this only works if the object I want to encode does not contain other objects inside, which is the case. How can I do to encode not only the "outer" object, but encode as well any members that are objects too?
The best method to serialize an object with private properties is to implement the \JsonSerializable interface and then implement your own JsonSerialize method to return the data you require to be serialized.
<?php
class Item implements \JsonSerializable
{
private $var;
private $var1;
private $var2;
public function __construct()
{
// ...
}
public function jsonSerialize()
{
$vars = get_object_vars($this);
return $vars;
}
}
json_encode will now serialize your object correctly.
If you're using php 5.4 you can use the JsonSerializable interface: http://www.php.net/manual/en/class.jsonserializable.php
You just implement a jsonSerialize method in your class which returns whatever you want to be encoded.
Then when you pass your object into json_encode, it'll encode the result of jsonSerialize.
Anyway. You need create public method in your class to return all their fields json encoded
public function getJSONEncode() {
return json_encode(get_object_vars($this));
}
I think #Petah's got the best approach, but that way you lose properties that are array or object. So I added a function wich do that recursively:
function json_encode_private($object) {
function extract_props($object) {
$public = [];
$reflection = new ReflectionClass(get_class($object));
foreach ($reflection->getProperties() as $property) {
$property->setAccessible(true);
$value = $property->getValue($object);
$name = $property->getName();
if(is_array($value)) {
$public[$name] = [];
foreach ($value as $item) {
if (is_object($item)) {
$itemArray = extract_props($item);
$public[$name][] = $itemArray;
} else {
$public[$name][] = $item;
}
}
} else if(is_object($value)) {
$public[$name] = extract_props($value);
} else $public[$name] = $value;
}
return $public;
}
return json_encode(extract_props($object));
}
EDIT: Added is_object() check inside the array loop to avoid a get_class() exception in the next extract_props() call when the array elements are not objects, like strings or numbers.
I think this may be a great case for the Usage of Traits
using the below guist I implemented jsonSerializable interface in multiple points of my app while keeping the code manageable
https://gist.github.com/zburgermeiszter/7dc5e65b06bb34a325a0363726fd8e14
trait JsonSerializeTrait
{
function jsonSerialize()
{
$reflect = new \ReflectionClass($this);
$props = $reflect->getProperties(\ReflectionProperty::IS_STATIC | \ReflectionProperty::IS_PUBLIC | \ReflectionProperty::IS_PROTECTED | \ReflectionProperty::IS_PRIVATE);
$propsIterator = function() use ($props) {
foreach ($props as $prop) {
yield $prop->getName() => $this->{$prop->getName()};
}
};
return iterator_to_array($propsIterator());
}
}
then you just have to do
class YourClass implements JsonSerializable
{
use JsonSerializeTrait;
... normal encapsulated code...
}
public function jsonSerialize()
{
$objectArray = [];
foreach($this as $key => $value) {
$objectArray[$key] = $value;
}
return json_encode($objectArray);
}
I personally think this is a way of doing it. It is similar to Petah's, except It keeps in line with encapsulation well, because the array is populated from the object.
Put this function in either your object or as a trait to be used by your object. To each their own though.
This would print a JSON with all of the properties (public, private and protected) of class foo:
$reflection = new ReflectionClass('Foo');
$properties = $reflection->getdefaultProperties();
echo json_encode($properties);
It would work from any context.
You can only encode an object's private members from within the class. As a side note though, does the json_enocde function not work for you? http://php.net/manual/en/function.json-encode.php
Using reflection you can json_encode private properties, although its not considered best practice:
function json_encode_private($object) {
$public = [];
$reflection = new ReflectionClass($object);
foreach ($reflection->getProperties() as $property) {
$property->setAccessible(true);
$public[$property->getName()] = $property->getValue($object);
}
return json_encode($public);
}
E.g.
class Foo {
public $a = 1;
public $b = 2;
}
class Bar {
private $c = 3;
private $d = 4;
}
var_dump(json_encode(new Foo()));
var_dump(json_encode_private(new Bar()));
Outputs:
string(13) "{"a":1,"b":2}"
string(13) "{"c":3,"d":4}"
http://codepad.viper-7.com/nCcKYW
Is there a way to make a read-only property of an object in PHP? I have an object with a couple arrays in it. I want to access them as I normally would an array
echo $objObject->arrArray[0];
But I don't want to be able to write to those arrays after they're constructed. It feels like a PITA to construct a local variable:
$arrArray = $objObject->getArray1();
echo $arrArray[0];
And anyways, while it keeps the array in the object pristine, it doesn't prevent me from re-writing the local array variable.
Well, the question is where do you want to prevent writing from?
The first step is making the array protected or private to prevent writing from outside of the object scope:
protected $arrArray = array();
If from "outside" of the array, a GETTER will do you fine. Either:
public function getArray() { return $this->arrArray; }
And accessing it like
$array = $obj->getArray();
or
public function __get($name) {
return isset($this->$name) ? $this->$name : null;
}
And accessing it like:
$array = $obj->arrArray;
Notice that they don't return references. So you cannot change the original array from outside the scope of the object. You can change the array itself...
If you really need a fully immutable array, you could use a Object using ArrayAccess...
Or, you could simply extend ArrayObject and overwrite all of the writing methods:
class ImmutableArrayObject extends ArrayObject {
public function append($value) {
throw new LogicException('Attempting to write to an immutable array');
}
public function exchangeArray($input) {
throw new LogicException('Attempting to write to an immutable array');
}
public function offsetSet($index, $newval) {
throw new LogicException('Attempting to write to an immutable array');
}
public function offsetUnset($index) {
throw new LogicException('Attempting to write to an immutable array');
}
}
Then, simply make $this->arrArray an instance of the object:
public function __construct(array $input) {
$this->arrArray = new ImmutableArrayObject($input);
}
It still supports most array like usages:
count($this->arrArray);
echo $this->arrArray[0];
foreach ($this->arrArray as $key => $value) {}
But if you try to write to it, you'll get a LogicException...
Oh, but realize that if you need to write to it, all you need to do (within the object) is do:
$newArray = $this->arrArray->getArrayCopy();
//Edit array here
$this->arrArray = new ImmutableArrayObject($newArray);
If you're using PHP 5+ you can do it with __set() and __get() methods.
You have to define how they work but should do just this.
Edit an example would be like this.
class Example {
private $var;
public function __get($v) {
if (is_array($v)) {
foreach () {
// handle it here
}
} else {
return $this->$v;
}
}
}
This might not be the "best" way of doing it but it'll work depending on what you need
If defined, the magic functions __get() and __set() will be called whenever a non-existing or private property is accessed. This can be used to create "get" and "set" methods for private properties, and for instance make them read-only or manipulate the data when stored or retrieved in it.
For instance:
class Foo
{
private $bar = 0;
public $baz = 4; // Public properties will not be affected by __get() or __set()
public function __get($name)
{
if($name == 'bar')
return $this->bar;
else
return null;
}
public function __set($name, $value)
{
// ignore, since Foo::bar is read-only
}
}
$myobj = new Foo();
echo $foo->bar; // Output is "0"
$foo->bar = 5;
echo $foo->bar; // Output is still "0", since the variable is read-only
See also the manual page for overloading in PHP.
For PHP 8.1+, you can use readonly properties:
class Test
{
public readonly array $arrArray;
public function __construct()
{
$this->arrArray = [1, 2, 3];
}
}
$test = new Test();
var_dump($test->arrArray); // OK
$test->arrArray = [4, 5, 6]; // Error
in the class, do this:
private $array;
function set_array($value) {
$this->array = $value;
}
then you just set like this:
$obj->set_array($new_array);
I am using PHP 5.2.x and want to encode objects of my custom PHP classes with only private members. One of the private members is an array of objects of another custom class.
I tried the solution outlined in https://stackoverflow.com/a/7005915/17716, but that obviously does not work recursively. The only solution that I can see is extending the json_encode method somehow ,so that the class' version of the json_encode method is called instead of the default method.
For reference, the code is as follows:
Class A {
private $x;
private $y;
private $z;
private $xy;
private $yz;
private $zx;
public function f1() {
...
}
public function f2() {
...
}
.
.
.
public function getJSONEncode() {
return json_encode(get_object_vars($this));
}
}
class B {
private $p; //This finally stores objects of class A
private $q;
private $r;
public function __construct() {
$this->p = array();
}
public function fn1() {
...
}
public function fn2() {
...
}
.
.
.
public function getJSONEncode() {
return json_encode(get_object_vars($this));
}
}
class C {
private $arr;
public function __construct() {
$this->arr = array();
}
public function fillData($data) {
$obj = new B();
//create objects of class B and fill in values for all variables
array_push($this->arr, $obj)
}
public function returnData() {
echo $this->arr[0]->getJSONEncode(); //Edited to add
}
}
What would be the best way to achieve this nested json encoding?
Edited to Add:
The output I get when the returnData method is executed is:
{"p":[{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{},{}],"q":"Lorem Ipsum","r":"Dolor Sit Amet"}
Whilst I believe you would be better off writing a proper export/encode function for each of your classes (which would construct a public object from both private and public values just for encoding - you could be quite clever and use php's reflection ability) - instead - you could make use of the following code:
/// example class B
class TestB {
private $value = 123;
}
/// example class A
class TestA {
private $prop;
public function __construct(){
$this->prop = new TestB();
}
}
function json_encode_private($obj){
/// export the variable to find the privates
$exp = var_export($obj, true);
/// get rid of the __set_state that only works 5.1+
$exp = preg_replace('/[a-z0-9_]+\:\:__set_state\(/i','((object)', $exp);
/// rebuild the object
eval('$enc = json_encode('.$exp.');');
/// return the encoded value
return $enc;
}
echo json_encode_private(new TestA());
/// {"prop":{"value":123}}
So the above should work, but I wouldn't recommend using eval anywhere in php - just because I always hear alarm bells quietly off in the distance :)
update
Just had a thought of what might make this a little safer, rather than using eval you could use create_function which would limit some of its creational powers, or at least the scope of those powers...
function json_encode_private($obj){
$exp = var_export($obj, true);
$exp = preg_replace('/[a-z0-9_]+\:\:__set_state\(/i','((object)', $exp);
$enc = create_function('','return json_encode('.$exp.');');
return $enc();
}
update 2
Had a chance to play around with another way of converting an object with private properties, to an object with public properties - using only a simple function (and no eval). The following would need to be tested on whichever version of PHP you are using as it's behaviour - again - might not be reliable.... due to the weird \0Class Name\0 prefixing in the converted private properties (see comments in code).
For more info on this strange prefixing behaviour:
http://uk3.php.net/language.types.array.php#language.types.array.casting
Anyway, so using a test class:
class RandomClass {
private $var = 123;
private $obj;
public function __construct(){
$this->obj = (object) null;
$this->obj->time = time();
}
}
We can use the following function to convert it to a public object:
function private_to_public( $a ){
/// grab our class, convert our object to array, build our return obj
$c = get_class( $a ); $b = (array) $a; $d = (object) null;
/// step each property in the array and move over to the object
/// usually this would be as simple as casting to an object, however
/// my version of php (5.3) seems to do strange things to private
/// properties when casting to an array... hence the code below:
foreach( $b as $k => $v ){
/// for some reason private methods are prefixed with a \0 character
/// and then the classname, followed by \0 before the actual key value.
/// This must be some kind of internal protection causing private
/// properties to be ignored. \0 is used by some languges to terminate
/// strings (not php though, as far as i'm aware).
if ( ord($k{0}) === 0 ) {
/// trim off the prefixed weirdnesss..?!
$e = substr($k, 1 + strlen($c) + 1);
/// unset the $k var first because it will remember the \0 even
/// if other values are assigned to it later on....?!
unset($k); $k = $e;
}
/// so if we have a key, either public or private - set our value on
/// the destination object.
if ( $k !== '' && $k !== NULL && $k !== FALSE ) {
$d->{$k} = $v;
}
}
return $d;
}
So if we put it all together:
$a = new RandomClass();
echo json_encode( private_to_public( $a ) );
/// {"var":123,"obj":{"time":1349777323}}
Again your best / most reliable bet is to either bespokely code your conversion methods for each class, or create some kind of generalised solution using Class Reflection, but that latter is far more involved, more involved than a StackOverflow answer... at least with the amount of time I have free ;)
further info
The above code will work when trying to access objects from anywhere, the reason for implementing this was because my first attempt was obviously to use the following:
echo json_encode( get_object_vars($a) );
/// you will get {} which isn't what you expect
It seems that if you want to use get_object_vars you have to use it from a context that has access to all the properties, i.e. from inside the class you are exposing:
public function getAllProperties(){
return get_object_vars( $this );
}
So, imagine we'd added the above to the RandomClass definition:
echo json_encode( $a->getAllProperties() );
/// you will get {"var":123,"obj":{"time":1349777323}}
This works because the members of a class have access to all the class's properties public or private.... so as I say, working this way is far far superior; superior, but not always possible.
This thread didn't helped me.
If I use
$class_vars = get_class_vars(get_class($this));
foreach ($class_vars as $name => $value) {
echo "$name : $value\n";
}
I get
attrib1_name : attrib2_name : attrib3_name
There are no values. Also a private attribute is shown, which I don't want.
If I use
echo "<pre>";
print_r(get_object_vars($this));
echo "</pre>";
I get
Array
(
[atrrib1_name] => attrib1_value
[attrib2_name] => attrib2_value
)
Here again I have a private attribute and all sub attributes. But this time I have the values. How can I constrain this to one level?
Isn't there a possibility to show all public attributes with their values of an object?
You are seeing non-public properties because get_class_vars works according to current scope. Since you are using $this your code is inside the class, so the non-public properties are accessible from the current scope. The same goes for get_object_vars which is probably a better choice here.
In any case, a good solution would be to move the code that retrieves the property values out of the class.
If you do not want to create a free function for that (why? seriously, reconsider!), you can use a trick that involves an anonymous function:
$getter = function($obj) { return get_object_vars($obj); };
$class_vars = $getter($this);
See it in action.
Update: Since you are in PHP < 5.3.0, you can use this equivalent code:
$getter = create_function('$obj', 'return get_object_vars($obj);');
$class_vars = $getter($this);
You can do this easily with php Reflection api
Extending Mr.Coder's answer, here is a snippet to fetch the public attributes of the object (name and value) as an array
public function getPublicProperties()
{
$results = [];
$reflectionObject = (new ReflectionObject($this));
$properties = $reflectionObject->getProperties(ReflectionProperty::IS_PUBLIC);
foreach ($properties as $property) {
$results[$property->getName()] = $property->getValue($this);
}
return $results;
}
Use get_object_vars.
see: http://dk.php.net/manual/en/function.get-object-vars.php
I Fully recognize what you are trying to achieve so why not have something external like this to help out... (pasted from PHPFiddle)
<?php
final class utils {
public static function getProperties(& $what) {
return get_object_vars($what);
}
}
class ball {
var $name;
private $x, $y;
function __construct($name,$x,$y) {
}
function publicPropsToArray() {
return utils::getProperties($this);
}
function allPropsToArray() {
return get_object_vars($this);
}
}
$ball1 = new ball('henry',5,6);
//$ball2 = new ball('henry',3,4);
echo "<pre>";
print_r($ball1->publicPropsToArray());
echo "\r\n\r\n";
print_r($ball1->allPropsToArray());
echo "\r\n\r\n";
?>
This way I can both access all properties of the object or for something such as a database access layer or similarly for a function that send "safe" data to a view or another un-privileged model I can send just the public properties, but have the behaviour defined within the object.
Sure this leads to coupling with a utility class, but to be fair not all couplings are bad, some are nesecarry to achieve an end goal, dont get bogged down by these things
Is there a way to make a read-only property of an object in PHP? I have an object with a couple arrays in it. I want to access them as I normally would an array
echo $objObject->arrArray[0];
But I don't want to be able to write to those arrays after they're constructed. It feels like a PITA to construct a local variable:
$arrArray = $objObject->getArray1();
echo $arrArray[0];
And anyways, while it keeps the array in the object pristine, it doesn't prevent me from re-writing the local array variable.
Well, the question is where do you want to prevent writing from?
The first step is making the array protected or private to prevent writing from outside of the object scope:
protected $arrArray = array();
If from "outside" of the array, a GETTER will do you fine. Either:
public function getArray() { return $this->arrArray; }
And accessing it like
$array = $obj->getArray();
or
public function __get($name) {
return isset($this->$name) ? $this->$name : null;
}
And accessing it like:
$array = $obj->arrArray;
Notice that they don't return references. So you cannot change the original array from outside the scope of the object. You can change the array itself...
If you really need a fully immutable array, you could use a Object using ArrayAccess...
Or, you could simply extend ArrayObject and overwrite all of the writing methods:
class ImmutableArrayObject extends ArrayObject {
public function append($value) {
throw new LogicException('Attempting to write to an immutable array');
}
public function exchangeArray($input) {
throw new LogicException('Attempting to write to an immutable array');
}
public function offsetSet($index, $newval) {
throw new LogicException('Attempting to write to an immutable array');
}
public function offsetUnset($index) {
throw new LogicException('Attempting to write to an immutable array');
}
}
Then, simply make $this->arrArray an instance of the object:
public function __construct(array $input) {
$this->arrArray = new ImmutableArrayObject($input);
}
It still supports most array like usages:
count($this->arrArray);
echo $this->arrArray[0];
foreach ($this->arrArray as $key => $value) {}
But if you try to write to it, you'll get a LogicException...
Oh, but realize that if you need to write to it, all you need to do (within the object) is do:
$newArray = $this->arrArray->getArrayCopy();
//Edit array here
$this->arrArray = new ImmutableArrayObject($newArray);
If you're using PHP 5+ you can do it with __set() and __get() methods.
You have to define how they work but should do just this.
Edit an example would be like this.
class Example {
private $var;
public function __get($v) {
if (is_array($v)) {
foreach () {
// handle it here
}
} else {
return $this->$v;
}
}
}
This might not be the "best" way of doing it but it'll work depending on what you need
If defined, the magic functions __get() and __set() will be called whenever a non-existing or private property is accessed. This can be used to create "get" and "set" methods for private properties, and for instance make them read-only or manipulate the data when stored or retrieved in it.
For instance:
class Foo
{
private $bar = 0;
public $baz = 4; // Public properties will not be affected by __get() or __set()
public function __get($name)
{
if($name == 'bar')
return $this->bar;
else
return null;
}
public function __set($name, $value)
{
// ignore, since Foo::bar is read-only
}
}
$myobj = new Foo();
echo $foo->bar; // Output is "0"
$foo->bar = 5;
echo $foo->bar; // Output is still "0", since the variable is read-only
See also the manual page for overloading in PHP.
For PHP 8.1+, you can use readonly properties:
class Test
{
public readonly array $arrArray;
public function __construct()
{
$this->arrArray = [1, 2, 3];
}
}
$test = new Test();
var_dump($test->arrArray); // OK
$test->arrArray = [4, 5, 6]; // Error
in the class, do this:
private $array;
function set_array($value) {
$this->array = $value;
}
then you just set like this:
$obj->set_array($new_array);