In PHP How to Access a ":Private" Array in an Object

In PHP how can I access a :private array in an object?

Change them to protected member variables and extend the class.

Whoever wrote the class with private members effectively made the class "final". Which goes to show that you should always write your members as protected, unless there's a really, REALLY good reason to do otherwise.

Hope that helps...

How can I access an array/object?

To access an array or object you how to use two different operators.

Arrays

To access array elements you have to use [].

echo $array[0];

On older PHP versions, an alternative syntax using {} was also allowed:

echo $array{0};

Difference between declaring an array and accessing an array element

Defining an array and accessing an array element are two different things. So don't mix them up.

To define an array you can use array() or for PHP >=5.4 [] and you assign/set an array/-element. While when you are accessing an array element with [] as mentioned above, you get the value of an array element opposed to setting an element.

//Declaring an array
$arrayA = array ( /*Some stuff in here*/ );
$arrayB = [ /*Some stuff in here*/ ]; //Only for PHP >=5.4

//Accessing an array element
echo $array[0];

Access array element

To access a particular element in an array you can use any expression inside [] or {} which then evaluates to the key you want to access:

$array[(Any expression)]

So just be aware of what expression you use as key and how it gets interpreted by PHP:

echo $array[0];            //The key is an integer; It accesses the 0's element
echo $array["0"];          //The key is a string; It accesses the 0's element
echo $array["string"];     //The key is a string; It accesses the element with the key 'string'
echo $array[CONSTANT];     //The key is a constant and it gets replaced with the corresponding value
echo $array[cOnStAnT];     //The key is also a constant and not a string
echo $array[$anyVariable]  //The key is a variable and it gets replaced with the value which is in '$anyVariable'
echo $array[functionXY()]; //The key will be the return value of the function

Access multidimensional array

If you have multiple arrays in each other you simply have a multidimensional array. To access an array element in a sub array you just have to use multiple [].

echo $array["firstSubArray"]["SecondSubArray"]["ElementFromTheSecondSubArray"]
         // ├─────────────┘  ├──────────────┘  ├────────────────────────────┘
         // │                │                 └── 3rd Array dimension;
         // │                └──────────────────── 2d  Array dimension;
         // └───────────────────────────────────── 1st Array dimension;

Objects

To access an object property you have to use ->.

echo $object->property;

If you have an object in another object you just have to use multiple -> to get to your object property.

echo $objectA->objectB->property;

Note:

1. Also you have to be careful if you have a property name which is invalid! So to see all problems, which you can face with an invalid property name see this question/answer. And especially this one if you have numbers at the start of the property name.

2. You can only access properties with public visibility from outside of the class. Otherwise (private or protected) you need a method or reflection, which you can use to get the value of the property.

Arrays & Objects

Now if you have arrays and objects mixed in each other you just have to look if you now access an array element or an object property and use the corresponding operator for it.

//Object
echo $object->anotherObject->propertyArray["elementOneWithAnObject"]->property;
    //├────┘  ├───────────┘  ├───────────┘ ├──────────────────────┘   ├──────┘
    //│       │              │             │                          └── property ; 
    //│       │              │             └───────────────────────────── array element (object) ; Use -> To access the property 'property'
    //│       │              └─────────────────────────────────────────── array (property) ; Use [] To access the array element 'elementOneWithAnObject'
    //│       └────────────────────────────────────────────────────────── property (object) ; Use -> To access the property 'propertyArray'
    //└────────────────────────────────────────────────────────────────── object ; Use -> To access the property 'anotherObject'

//Array
echo $array["arrayElement"]["anotherElement"]->object->property["element"];
    //├───┘ ├────────────┘  ├──────────────┘   ├────┘  ├──────┘ ├───────┘
    //│     │               │                  │       │        └── array element ; 
    //│     │               │                  │       └─────────── property (array) ; Use [] To access the array element 'element'
    //│     │               │                  └─────────────────── property (object) ; Use -> To access the property 'property'
    //│     │               └────────────────────────────────────── array element (object) ; Use -> To access the property 'object'
    //│     └────────────────────────────────────────────────────── array element (array) ; Use [] To access the array element 'anotherElement'
    //└──────────────────────────────────────────────────────────── array ; Use [] To access the array element 'arrayElement'

I hope this gives you a rough idea how you can access arrays and objects, when they are nested in each other.

Note:

1. If it is called an array or object depends on the outermost part of your variable. So [new StdClass] is an array even if it has (nested) objects inside of it and $object->property = array(); is an object even if it has (nested) arrays inside.

   And if you are not sure if you have an object or array, just use gettype().

2. Don't get yourself confused if someone uses another coding style than you:

    //Both methods/styles work and access the same data
    echo $object->anotherObject->propertyArray["elementOneWithAnObject"]->property;
    echo $object->
           anotherObject
           ->propertyArray
           ["elementOneWithAnObject"]->
           property;
   
    //Both methods/styles work and access the same data
    echo $array["arrayElement"]["anotherElement"]->object->property["element"];
    echo $array["arrayElement"]
        ["anotherElement"]->
            object
      ->property["element"];
   

Arrays, Objects and Loops

If you don't just want to access a single element you can loop over your nested array / object and go through the values of a particular dimension.

For this you just have to access the dimension over which you want to loop and then you can loop over all values of that dimension.

As an example we take an array, but it could also be an object:

Array (
    [data] => Array (
            [0] => stdClass Object (
                    [propertyXY] => 1
                )    
            [1] => stdClass Object (
                    [propertyXY] => 2
                )   
            [2] => stdClass Object (
                    [propertyXY] => 3                   
               )    
        )
)

If you loop over the first dimension you will get all values from the first dimension:

foreach($array as $key => $value)

Means here in the first dimension you would only have 1 element with the key($key) data and the value($value):

Array (  //Key: array
    [0] => stdClass Object (
            [propertyXY] => 1
        )
    [1] => stdClass Object (
            [propertyXY] => 2
        )
    [2] => stdClass Object (
            [propertyXY] => 3
        )
)

If you loop over the second dimension you will get all values from the second dimension:

foreach($array["data"] as $key => $value)

Means here in the second dimension you would have 3 element with the keys($key) 0, 1, 2 and the values($value):

stdClass Object (  //Key: 0
    [propertyXY] => 1
)
stdClass Object (  //Key: 1
    [propertyXY] => 2
)
stdClass Object (  //Key: 2
    [propertyXY] => 3
)

And with this you can loop through any dimension which you want no matter if it is an array or object.

Analyse var_dump() / print_r() / var_export() output

All of these 3 debug functions output the same data, just in another format or with some meta data (e.g. type, size). So here I want to show how you have to read the output of these functions to know/get to the way how to access certain data from your array/object.

Input array:

$array = [
    "key" => (object) [
        "property" => [1,2,3]
    ]
];

var_dump() output:

array(1) {
  ["key"]=>
  object(stdClass)#1 (1) {
    ["property"]=>
    array(3) {
      [0]=>
      int(1)
      [1]=>
      int(2)
      [2]=>
      int(3)
    }
  }
}

print_r() output:

Array
(
    [key] => stdClass Object
        (
            [property] => Array
                (
                    [0] => 1
                    [1] => 2
                    [2] => 3
                )

        )

)

var_export() output:

array (
  'key' => 
  (object) array(
     'property' => 
    array (
      0 => 1,
      1 => 2,
      2 => 3,
    ),
  ),
)

So as you can see all outputs are pretty similar. And if you now want to access the value 2 you can just start from the value itself, which you want to access and work your way out to the "top left".

1. We first see, that the value 2 is in an array with the key 1

// var_dump()
array(3) {
  [0]=>
  int(1)
  [1]=>
  int(2)    // <-- value we want to access
  [2]=>
  int(3)
}

// print_r()
Array
(
    [0] => 1
    [1] => 2    // <-- value we want to access
    [2] => 3
)

// var_export()
array (
  0 => 1,
  1 => 2,    // <-- value we want to access
  2 => 3,
)

This means we have to use [] to access the value 2 with [1], since the value has the key/index 1.

2. Next we see, that the array is assigned to a property with the name property of an object

// var_dump()
object(stdClass)#1 (1) {
  ["property"]=>
  /* Array here */
}

// print_r()
stdClass Object
(
    [property] => /* Array here */
)

// var_export()
(object) array(
    'property' => 
  /* Array here */
),

This means we have to use -> to access the property of the object, e.g. ->property.

So until now, we know that we have to use ->property[1].

3. And at the end we see, that the outermost is an array

// var_dump()
array(1) {
  ["key"]=>
  /* Object & Array here */
}

// print_r()
Array
(
    [key] => stdClass Object
        /* Object & Array here */
)

// var_export()
array (
  'key' => 
  /* Object & Array here */
)

As we know that we have to access an array element with [], we see here that we have to use ["key"] to access the object. We now can put all these parts together and write:

echo $array["key"]->property[1];

And the output will be:

2

Don't let PHP troll you!

There are a few things, which you have to know, so that you don't spend hours on it finding them.

1. "Hidden" characters

   Sometimes you have characters in your keys, which you don't see on the first look in the browser. And then you're asking yourself, why you can't access the element. These characters can be: tabs (\t), new lines (\n), spaces or html tags (e.g. </p>, <b>), etc.

   As an example if you look at the output of print_r() and you see:

   Array ( [key] => HERE ) 
   

   Then you are trying to access the element with:

   echo $arr["key"];
   

   But you are getting the notice:

   Notice: Undefined index: key

   This is a good indication that there must be some hidden characters, since you can't access the element, even if the keys seems pretty correct.

   The trick here is to use var_dump() + look into your source code! (Alternative: highlight_string(print_r($variable, TRUE));)

   And all of the sudden you will maybe see stuff like this:

   array(1) {
       ["</b>
   key"]=>
       string(4) "HERE"
   }
   

   Now you will see, that your key has a html tag in it + a new line character, which you didn't saw in the first place, since print_r() and the browser didn't showed that.

   So now if you try to do:

   echo $arr["</b>\nkey"];
   

   You will get your desired output:

   HERE
   

2. Never trust the output of print_r() or var_dump() if you look at XML

   You might have an XML file or string loaded into an object, e.g.

   <?xml version="1.0" encoding="UTF-8" ?> 
   <rss> 
       <item> 
           <title attribute="xy" ab="xy">test</title> 
       </item> 
   </rss>
   

   Now if you use var_dump() or print_r() you will see:

   SimpleXMLElement Object
   (
       [item] => SimpleXMLElement Object
       (
           [title] => test
       )
   
   )
   

   So as you can see you don't see the attributes of title. So as I said never trust the output of var_dump() or print_r() when you have an XML object. Always use asXML() to see the full XML file/string.

   So just use one of the methods shown below:

   echo $xml->asXML();  //And look into the source code
   
   highlight_string($xml->asXML());
   
   header ("Content-Type:text/xml");
   echo $xml->asXML();
   

   And then you will get the output:

   <?xml version="1.0" encoding="UTF-8"?>
   <rss> 
       <item> 
           <title attribute="xy" ab="xy">test</title> 
       </item> 
   </rss>
   

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For more information see:

General (symbols, errors)

• Reference — What does this symbol mean in PHP?
• Reference - What does this error mean in PHP?
• PHP parse/syntax errors; and how to solve them

Property name problems

• How can I access a property with an invalid name?
• How to access object properties with names like integers or invalid property names?

php how to access object array

Something like this maybe:

$object->_items[index]->_productId

But if _items is private you will need a public getter or mess with the Reflection classes. You can set the the private property to be accessible through ReflectionProperty
Try this:

    $reflectionObject = new ReflectionObject($yourObject);
    $property = $reflectionObject->getProperty('_items');
    $property->setAccessible(true);
    $items = $property->getValue($yourObject);

Accessing private value in array, converted from object

If you have a look at the documentation on converting to an array, it states:

private variables have the class name prepended to the variable name; protected variables have a '*' prepended to the variable name. These prepended values have null bytes on either side.

This means that it's not A that's prepended, but \0A\0. So the key would be "\0A\0val".

Cannot access private property

Student->name is a private data member. That means, by definition, you cannot access it outside of the definition of Student. That's basically the purpose of getName(), so you CAN access it outside the definition.

What you want to do is this:

foreach($this->students as $key=>$value){
    echo $value->getName() . " ";
}

This will act as expected.

If you want to know more about access modifiers, you can read about them here.

Array and object issue in symfony

Define your getters, and then use them.

for example in this

foreach ($productos as $producto) 
{ $id = $producto->id; echo $id; }

Try

$producto->getId(); 

instead of

 $producto->id;

assuming you defined your getter.

How can i access a private property in Object

First of all, I am sorry I didn't use couchbase PHP, but here is how you can create a Getter and Setter method for a Private variable, hope you can implement it

<?php

class Student {
    private $sName;

    public function setName($name) {
        $this->sName = $name;
    }

    public function getName() {
        return $this->sName;
    }
}

$student = new Student;                     // create an object
//$student->sName = "error";                // this makes an error while it is Private: Fatal error: Uncaught Error: Cannot access private property
//echo $student->sName;                     // this makes an error while it is Private: Fatal error: Uncaught Error: Cannot access private property
$student->setName("MisterniceGuy"); // Set student name
echo $student->getName();                   // MisterniceGuy

?>

PHP Undefined Index for 2D private array

The member "data" is just a normal array, your are loosing dimensions because of the way pthreads objects work; you don't want to use the member "data", it is not necessary:

<?php
class File extends Stackable {

    /* in pthreads you are responsible for the objects you create */
    /* so we accept an array by reference to store dimensions */

    public function set_data($array, &$files){
         foreach($array as $row => $data) {
            foreach($data as $col => $val) {
                 /* force this vector into existence */
                 if (!isset($this[$row])) {
                    $this[$row] = $files[] = new File();
                 }
                 $this[$row][$col]=$val;
            }
         }                  
    } 

    public function run() {}
}

$files = array();

$f = new File();
$f->set_data(array("test" => array($_SERVER)), $files);

var_dump($f);
?>

You should bear in mind that pthreads objects have the overhead of safety to contend with, so loop over their members as little as possible, in an ideal world, the $array coming to setData would already be of a suitable type ...

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