PHP 5.4.31 Released

اشیا

مقدار اولیه برای اشیا

برای ساخت یک object جدید از جمله new برای نمونه‌سازی یک کلاس استفاده نمایید:

<?php
class foo
{
    function 
do_foo()
    {
        echo 
"Doing foo."
    }
}

$bar = new foo;
$bar->do_foo();
?>

برای بحث کامل کلاس‌ها و اشیا را ببینید.

تبدیل به شی

اگر یک object به object تبدیل شود تغییر داده نمی‌شود. اگر یک مقدار از هر نوع دیگری به یک object تبدیل شود یک نمونه جدید کلاس داخلی stdClass ساخته می‌شود. اگر مقدار NULL, باشد نمونه جدید خالی خواهد بود. Array در تبدیل به object یک شی با ویژگی‌های کلیدها و مقدار متناسب با آنها را خواهد ساخت. برای هر مقدار دیگری یک عضو متغیر با نام scalar حاوی مقدار است.

<?php
$obj 
= (object) 'ciao';
echo 
$obj->scalar;  // outputs 'ciao'
?>
add a note add a note

User Contributed Notes 23 notes

up
15
gabe at fijiwebdesign dot com
7 years ago
In response to sirbinam.
You cannot call a function or method before it exists. In your example, the global instance of stdout is just being passed around to differnet references (pointers). It however exists in the "dump" function scope via the global keyword.

The code below works fine and illustrates that "stdout" has been defined before its instantiation.

<?php

class profiler{
  function
profiler(){
   
$this->starttime = microtime();
  }

  function
dump(){
    global
$stdout;
   
$this->endtime = microtime();
   
$duration = $this->endtime - $this->starttime;
   
$stdout->write($duration);
  }
}

class
stdout{
  function
write($msg){
    echo
$msg;
  }
}

$stdout =& new stdout();
$profiler =& new profiler();
$profiler->dump();

?>

All classes and functions declarations within a scope exist even before the php execution reaches them. It does not matter if you have your classes defined on the first or last line, as long as they are in the same scope as where they are called and are not in a conditional statement that has not been evaluated yet.
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10
Mithras
5 years ago
In response to harmor: if an array contains another array as a value, you can recursively convert all arrays with:

<?php
function arrayToObject( $array ){
  foreach(
$array as $key => $value ){
    if(
is_array( $value ) ) $array[ $key ] = arrayToObject( $value );
  }
  return (object)
$array;
}
?>
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9
helpful at stranger dot com
2 years ago
By far the easiest and correct way to instantiate an empty generic php object that you can then modify for whatever purpose you choose:

<?php $genericObject = new stdClass(); ?>

I had the most difficult time finding this, hopefully it will help someone else!
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9
qeremy [atta] gmail [dotta] com
2 years ago
Do you remember some JavaScript implementations?

// var timestamp = (new Date).getTime();

Now it's possible with PHP 5.4.*;

<?php
class Foo
{
    public
$a = "I'm a!";
    public
$b = "I'm b!";
    public
$c;
   
    public function
getB() {
        return
$this->b;
    }
   
    public function
setC($c) {
       
$this->c = $c;
        return
$this;
    }
   
    public function
getC() {
        return
$this->c;
    }
}

print (new
Foo)->a;      // I'm a!
print (new Foo)->getB(); // I'm b!
?>

or

<?php
// $_GET["c"] = "I'm c!";
print (new Foo)
       ->
setC($_GET["c"])
       ->
getC(); // I'm c!
?>
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8
mailto dot aurelian at gmail dot com
4 years ago
You can create [recursive] objects with something like:
<?php
  $literalObjectDeclared
= (object) array(
    
'foo' => (object) array(
         
'bar' => 'baz',
         
'pax' => 'vax'
     
),
     
'moo' => 'ui'
  
);
print
$literalObjectDeclared->foo->bar; // outputs "baz"!
?>
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6
cFreed at orange dot fr
5 years ago
CAUTION:
"Arrays convert to an object with properties named by keys, and corresponding values".

This is ALWAYS true, which means that even numeric keys are accepted when converting.
But the resulting properties cannot be accessed, since they don't match the variables naming rules.

So this:
<?php
$x
= (object) array('a'=>'A', 'b'=>'B', 'C');
echo
'<pre>'.print_r($x, true).'</pre>';
?>
works and displays:
stdClass Object
(
    [a] => A
    [b] => B
    [0] => C
)

But this:
<?php
echo '<br />'.$x->a;
echo
'<br />'.$x->b;
echo
'<br />'.$x->{0}; # (don't use $x->0, which is obviously a syntax error)
?>
fails and displays:
A
B
Notice: Undefined property: stdClass::$0 in...
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4
bob
6 years ago
Why is there nothing in the docs about instantiating a generic object?  ie new object() - it does not work.

If one wants to create a dynamic object on the fly, the only option I see is to create it implicitly, by creating a child of it - ghetto:

unset($obj);
$obj->blah = 3;
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1
Cosmitar: mhherrera31 at hotmail
3 years ago
i would like to share a curious behavior on casted objects. Casting an object from a class with private/protected attributes results a stdClass with a private/protected attribute for get.
Example:
<?PHP
class Foo{
private
$priv = 1;
public
$pub = 2;
public function
getSimple(){
  return (object)(array)
$this; //the array cast is to force a stdClass result
}
}
$bar = new Foo();
var_dump($bar->getSimple();// output: object(stdClass)#3 (2) { ["priv:private"]=> int(1) ["pub"]=> int(2) }

var_dump($bar->getSimple()->priv);// output: NULL, not a Fatal Error
var_dump($bar->getSimple()->pub);// output: int(2)

$barSimple = $bar->getSimple();
$barSimple->priv = 10;
var_dump($barSimple->priv);// output: int(10)

?>
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0
Ashley Dambra
5 months ago
Here a new updated version of 'stdObject' class. It's very useful when extends to controller on MVC design pattern, user can create it's own class.

Hope it help you.

<?php
class stdObject {
    public function
__construct(array $arguments = array()) {
        if (!empty(
$arguments)) {
            foreach (
$arguments as $property => $argument) {
               
$this->{$property} = $argument;
            }
        }
    }

    public function
__call($method, $arguments) {
       
$arguments = array_merge(array("stdObject" => $this), $arguments); // Note: method argument 0 will always referred to the main class ($this).
       
if (isset($this->{$method}) && is_callable($this->{$method})) {
            return
call_user_func_array($this->{$method}, $arguments);
        } else {
            throw new
Exception("Fatal error: Call to undefined method stdObject::{$method}()");
        }
    }
}

// Usage.

$obj = new stdObject();
$obj->name = "Nick";
$obj->surname = "Doe";
$obj->age = 20;
$obj->adresse = null;

$obj->getInfo = function($stdObject) { // $stdObject referred to this object (stdObject).
   
echo $stdObject->name . " " . $stdObject->surname . " have " . $stdObject->age . " yrs old. And live in " . $stdObject->adresse;
};

$func = "setAge";
$obj->{$func} = function($stdObject, $age) { // $age is the first parameter passed when calling this method.
   
$stdObject->age = $age;
};

$obj->setAge(24); // Parameter value 24 is passing to the $age argument in method 'setAge()'.

// Create dynamic method. Here i'm generating getter and setter dynimically
// Beware: Method name are case sensitive.
foreach ($obj as $func_name => $value) {
    if (!
$value instanceOf Closure) {

       
$obj->{"set" . ucfirst($func_name)} = function($stdObject, $value) use ($func_name) {  // Note: you can also use keyword 'use' to bind parent variables.
           
$stdObject->{$func_name} = $value;
        };

       
$obj->{"get" . ucfirst($func_name)} = function($stdObject) use ($func_name) {  // Note: you can also use keyword 'use' to bind parent variables.
           
return $stdObject->{$func_name};
        };

    }
}

$obj->setName("John");
$obj->setAdresse("Boston");

$obj->getInfo();
?>
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0
wyattstorch42 at outlook dot com
6 months ago
If you call var_export() on an instance of stdClass, it attempts to export it using ::__set_state(), which, for some reason, is not implemented in stdClass.

However, casting an associative array to an object usually produces the same effect (at least, it does in my case). So I wrote an improved_var_export() function to convert instances of stdClass to (object) array () calls. If you choose to export objects of any other class, I'd advise you to implement ::__set_state().

<?php
/**
* An implementation of var_export() that is compatible with instances
* of stdClass.
* @param mixed $variable The variable you want to export
* @param bool $return If used and set to true, improved_var_export()
*     will return the variable representation instead of outputting it.
* @return mixed|null Returns the variable representation when the
*     return parameter is used and evaluates to TRUE. Otherwise, this
*     function will return NULL.
*/
function improved_var_export ($variable, $return = false) {
    if (
$variable instanceof stdClass) {
       
$result = '(object) '.improved_var_export(get_object_vars($variable), true);
    } else if (
is_array($variable)) {
       
$array = array ();
        foreach (
$variable as $key => $value) {
           
$array[] = var_export($key, true).' => '.improved_var_export($value, true);
        }
       
$result = 'array ('.implode(', ', $array).')';
    } else {
       
$result = var_export($variable, true);
    }

    if (!
$return) {
        print
$result;
        return
null;
    } else {
        return
$result;
    }
}

// Example usage:
$obj = new stdClass;
$obj->test = 'abc';
$obj->other = 6.2;
$obj->arr = array (1, 2, 3);

improved_var_export((object) array (
   
'prop1' => true,
   
'prop2' => $obj,
   
'assocArray' => array (
       
'apple' => 'good',
       
'orange' => 'great'
   
)
));

/* Output:
(object) array ('prop1' => true, 'prop2' => (object) array ('test' => 'abc', 'other' => 6.2, 'arr' => array (0 => 1, 1 => 2, 2 => 3)), 'assocArray' => array ('apple' => 'good', 'orange' => 'great'))
*/
?>

Note: This function spits out a single line of code, which is useful to save in a cache file to include/eval. It isn't formatted for readability. If you want to print a readable version for debugging purposes, then I would suggest print_r() or var_dump().
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1
info at keltoi-web dot com
10 years ago
PHP supports recursive type definitions as far as I've tried. The class below (a _very_ simple tree) is an example:

class Tree {

var $_value = null;
var $_children = array();

function Tree ($value) {
  $this->_value = $value;
}

function addChild ($value) {
  $aux_node = new Tree ($value);
  $this->_children [] = $aux_node;
  return $aux_node;
}
}

As you can see, in addChild we reference Tree again...

However, you must be careful about references. See the chapter "References explained" for more details.

Hope this helps.
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0
Trevor Blackbird > yurab.com
8 years ago
You can create a new object using the built-in stdClass or by using type-casting:

<?php

// This is the proper way
$object1 = new stdClass();

// This works too
$object2 = (object) NULL;

// This will create an object from an array
$monkey_array = array('title'=>'Spider Monkey', 'src'=>'monkey.jpg');
$monkey_object = (object) $monkey_array;
print
$monkey_object->title . ' ' . $monkey_object->src;

// You can type-cast in the middle of an expression
function customHTML($some_object) {
// this function expects an object as the argument and returns some output
}
print
'<p>Writing some output ' . customHTML( (object) array('rows'=>3, 'cols'=>4) );

?>
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0
mortoray at ecircle-ag dot com
9 years ago
If you use new to create items in an array, you may not get the results you want since the parameters to array will be copies of the original and not references.

By Example:
class Store {
    var $item = 3;
}

    $a = array( new Store() );
    $b = $a;
    $a[0]->item = 2;
    print( "|" . $b[0]->item . "| <br>" );   //shows 3

    $a = array();
    $a[] =& new Store();
    $b = $a;
    $a[0]->item = 2;
    print( "|" . $b[0]->item . "| <br>" );   //shows 2

This is extremely important if you intend on passing arrays of classes to functions and expect them to always use the same object instance!

Note: The following syntax is desired (or maybe even the default notation should translate as this):
   $a = array( &new Store() );
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-2
ludvig dot ericson at gmail dot com
7 years ago
In reply to the usort thing, you can access a property of an object dynamically by:
<?php
$obj
= (object)array("Test" => "bar")
$var = "Test";
echo
$obj->$var;
?>
This will output "bar", and do notice I call on ->$var and not just ->var.
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-2
iblun at gmx dot net
9 years ago
To sort an array, that contains an object, after one fieldname inside the object, im using this function:

function objectSort($objectarray, $field)
{
    for ($a=0;$a < (count($objectarray)); $a++)
    {
        for ($b=0;$b < (count($objectarray)); $b++)
        {   
            if ($objectarray[$a]->$field < $objectarray[$b]->$field)
            {
                $temp = $objectarray[$a];
                $objectarray[$a] = $objectarray[$b];
                $objectarray[$b] = $temp;
            }
        }
    }
   
    return $objectarray;
}
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-3
spidgorny at gmail dot com
5 years ago
If having

class BugDetails extends Bug

you want to cast an object of a Bug to BugDetails like this
<?php
    $clone
= (BugDetails) clone $this;
// OR
   
$clone = (BugDetails) $bug;
?>
which doesn't work in PHP, you have two options:
1. Copying all (including private) properties manually (you could also use get_object_vars(), but this is shorter):
<?php
    $clone
= new BugDetails();
    foreach (
$this as $key => $val) {
       
$clone->$key = $val;
    }
?>
2. Serialize an object Bug, manipulate the resulting string so that it has BugDetails inside and unserialize it.
See here: http://blog.adaniels.nl/articles/a-dark-corner-of-php-class-casting/

Spent two hours looking for more elegant solution, that's my findings.
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-4
nconantj
10 years ago
php at electricsurfer.com,

More than a year later and here's some clarification of what's happening in your code, via comments in an otherwise verbatim copy.

<?
class c
{
   var $a = array('a'=>'aa','b'=>'ab');
   var $b = 'c';
 
   function show()
   {
       echo $this->a['a']; // -> 1st
       echo $this->a['b']; // outputs 'ab'
     
       $a = 'a';
       $b = 'b';
     
       echo $this->$a[$a]; // [] 1st, not what I expected
       //Above first becomes $this->$a['a'] by looking at the function's local $a
       //Next it becomes $this->a by again looking at the function's local $a, which references the class variable $a with no subscripts.
       // In order to reference elements of the class variable $a,
       // you want to use $this->a[$a]

       echo $this->$a[$b]; // does NOT output 'ab'
       // Same as above, but the first step $b becomes 'b'

       $this_a =& $this->$a; // work-around
     
       echo $this_a[$a]; // no question
       echo $this_a[$b];
     
       $a_arr = array('a'=>'b');
     
       echo $this->$a_arr[$a]; // [] 1st => outputs 'c'
       // This becomes $this->$a_arr['a'] which becomes $this->c,
       // by referencing the local variables first.
   }
}
$c = new c();
$c->show();
?>
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-5
Anonymous
4 years ago
Initialization, Instantiation and Instances are terms that can be confusing at first. Let's try to sort it out starting with this simple class definition.

<?php

class User
{
  public
$first_name;
  public
$last_name;

  public function
__toString()
  {
    return
"User [first='$this->first_name', last='$this->last_name']";
  }
}

?>

Now create several INSTANCES of User by INSTANTIATING the User class above.

<?php
$user_1
= new User;        // $user_1 is an INSTANCE of User
$user_2 = new User;        // $user_2 is an INSTANCE of User
echo $user_1 . '<br>';     // User [first='', last='']
echo $user_2 . '<br>';     // User [first='', last='']
?>

Here we have (2) two INSTANCES of User, but each instance was only INSTANTIATED once - when we used the 'new' operator.

And now looking at the printed output, you can see there are no values for their first or last names. This means that the objects themselves have NOT been INITIALIZED. To remedy this situation, rewrite the class definition by adding a __construct() method.

<?php

class User
{
  public
$first_name;
  public
$last_name;

  public function
__construct($first, $last)    // Require first and last names when INSTANTIATING
 
{
   
$this->first_name = $first;                 // INITIALIZE $first_name;
   
$this->last_name = $last;                   // INITIALIZE $last_name;
 
}

  public function
__toString()
  {
    return
"User [first='$this->first_name', last='$this->last_name']";
  }
}

?>

Now try it again.

<?php
$user_1
= new User('John', 'Doe');      // $user_i is an INSTANCE of User 
$user_2 = new User('Jane', 'Doe');      // $user_2 is an INSTANCE of User
echo $user_1 . '<br>';                  // prints: User [first='John', last='Doe']
echo $user_2 . '<br>';                  // prints: User [first='Jane', last='Doe']
?>

The __construct() method is called automatically by PHP when it sees the 'new' operator. Our __construct() method above requires the first and last names to be passed in as arguments and uses them to INITIALIZE objects when INSTANTIATING new INSTANCES.
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-5
Isaac Z. Schlueter i at foohack dot com
5 years ago
In response to Harmor and Mithras,  you can use the json functions to convert multi-dimensional arrays to objects very reliably.

Also, note that just using (object)$x doesn't allow you to access properties inline.  For example, this is invalid:

<?php
$x
= array("foo"=>"bar");
echo ((object)
$x)->foo; // PHP Parse error, unexpected T_OBJECT_OPERATOR
?>

However, this function will let you do that, and will also handle multi-dimensional arrays without any hassle.

<?php
function to_object ($x) {
    return (
is_object($x) || is_array($x)) ? json_decode(json_encode($x)) : (object) $x;
}

echo
to_object( array("foo"=>"bar") )->foo; // "bar"
?>

Note that *numeric* arrays will not be converted to objects using this method.
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-7
Rick
6 years ago
Bob, I think you solution is to use stdClass and add properties on the fly...

$obj = new stdClass();
$obj->data ="This is the solution";
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-7
wbcarts at juno dot com
5 years ago
ON-THE-FLY!!!

In response to Bobs note below (and Rick's somewhat): It is much better to predefine the object you want to create. This is because in all the programs you write, you will still create objects On-the-Fly anyway:

$foo = 'My String Object';      // on-the-fly!
$bar = 45;                      // on-the-fly!
$obj = new stdClass();          // on-the-fly!
$obj->blah = 3;                 // on-the-fly!

So what's missing above? Real control over WHAT your program does, HOW it does it, and HOW your data is organized. Let's say your code $obj->blah = 3 was 'blah' because 3 was your last Test Score (take no offense, I've done worse!). In that case, you could use code like so:

<?php

class Test{
  const
MIN = 0, MAX = 100;     // acceptable range for a test

 
protected $person;            // person taking the test
 
protected $score;             // use the word 'score' because 'blah' is meaningless

 
public function __construct($p, $s){
   
$this->person = $p;
   
$this->score = self::clamp($s);
  }

  protected static function
clamp($val){
    if(
$val < self::MIN) $val = self::MIN;
    if(
$val > self::MAX) $val = self::MAX;
    return
$val;
  }

  public function
__toString(){
    return
"Test [person=$this->person, score=$this->score%]";
  }
}

$obj = new Test("John Doe", 83);    // on-the-fly!
echo (object)$obj;                  // outputs 'Test [person=John Doe, score=83%]'
?>

Writing your own class definitions help maintain the "integerity" of your objects - see how the clamp() function keeps test scores between 0 and 100 percent? PHP  uses similar techniques to set min and max vals on Numbers. And, classes like Test are way more useful than objects created with an empty shell, uh em, stdClass. In addition, you can see WHAT, WHERE, WHY, and HOW your program actually works... On-the-Fly!

-->
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-2
Ashley Dambra
5 months ago
Class like stdClass but with the possibility to add and execute function.

class stdObject {
    public function __construct(array $arguments = array()) {
        if (!empty($arguments)) {
            foreach ($arguments as $property => $argument) {
                if ($argument instanceOf Closure) {
                    $this->{$property} = $argument;
                } else {
                    $this->{$property} = $argument;
                }
            }
        }
    }

    public function __call($method, $arguments) {
        if (isset($this->{$method}) && is_callable($this->{$method})) {
            return call_user_func_array($this->{$method}, $arguments);
        } else {
            throw new Exception("Fatal error: Call to undefined method stdObject::{$method}()");
        }
    }
}
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-10
razvan_zarzu at yahoo dot com
2 years ago
In PHP 5.3.6, even if the following code doesn't have any apparent syntax errors:

<?php
class Test {
  public
$a = SplFixedArray::fromArray(array());
}
?>

, the result is:

Parse error: syntax error, unexpected '(', expecting ',' or ';' in ~\test.php on line 3

This is because on an implicit object initialization of $a, which is not allowed in PHP.
Hope this helps someone.
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