mysqli_result::fetch_object

mysqli_fetch_object

(PHP 5, PHP 7, PHP 8)

mysqli_result::fetch_object -- mysqli_fetch_objectDevuelve la fila actual de un conjunto de resultados como un objeto

Descripción

Estilo orientado a objetos

mysqli_result::fetch_object(string $class_name = "stdClass", array $params = ?): object

Estilo por procedimientos

mysqli_fetch_object(mysqli_result $result, string $class_name = "stdClass", array $params = ?): object

mysqli_fetch_object() devolverá la fila actual del conjunto de resultados como un objeto, donde los atributos del objeto representan los nombres de los campos encontrados en el conjunto de resultados.

Observe que mysqli_fetch_object() establece las propiedades del objeto antes de llamar al constructor del objeto.

Parámetros

result

Sólo estilo por procedimientos: Un conjunto de identificadores de resultados devuelto por mysqli_query(), mysqli_store_result() o mysqli_use_result().

class_name

El nombre de la clase a instanciar, establecer las propiedades y devolver. Si no se especifica se devuelve un objeto stdClass.

params

Un array opcional de parámetros para pasar al constructor de los objetos de class_name.

Valores devueltos

Devuelve un objeto con las propiedades de cadena que corresponden a la fila obtenida o null si no hay más filas en el conjunto de resultados.

Nota: Los nombres de los campos devueltos por esta función son sensibles a mayúsculas y minúsculas.

Nota: Esta función define campos NULOS al valor null de PHP.

Ejemplos

Ejemplo #1 Estilo orientado a objetos

<?php
$mysqli
= new mysqli("localhost", "mi_usuario", "mi_contraseña", "world");

/* comprobar la conexión */
if (mysqli_connect_errno()) {
printf("Falló la conexión: %s\n", mysqli_connect_error());
exit();
}

$consulta = "SELECT Name, CountryCode FROM City ORDER by ID DESC LIMIT 50,5";

if (
$resultado = $mysqli->query($consulta)) {

/* obtener el array de objetos */
while ($obj = $resultado->fetch_object()) {
printf ("%s (%s)\n", $obj->Name, $obj->CountryCode);
}

/* liberar el conjunto de resultados */
$resultado->close();
}

/* cerrar la conexión */
$mysqli->close();
?>

Ejemplo #2 Estilo por procedimientos

<?php
$enlace
= mysqli_connect("localhost", "mi_usuario", "mi_contraseña", "world");

/* comprobar la conexión */
if (mysqli_connect_errno()) {
printf("Falló la conexión: %s\n", mysqli_connect_error());
exit();
}

$consulta = "SELECT Name, CountryCode FROM City ORDER by ID DESC LIMIT 50,5";

if (
$resultado = mysqli_query($enlace, $consulta)) {

/* obtener el array asociativo */
while ($obj = mysqli_fetch_object($resultado)) {
printf ("%s (%s)\n", $obj->Name, $obj->CountryCode);
}

/* liberar el conjunto de resultados */
mysqli_free_result($resultado);
}

/* cerrar la conexión */
mysqli_close($enlace);
?>

El resultado de los ejemplos sería:

Pueblo (USA)
Arvada (USA)
Cape Coral (USA)
Green Bay (USA)
Santa Clara (USA)

Ver también

add a note add a note

User Contributed Notes 9 notes

up
16
object-array at gmail dot com
8 years ago
Please mind the difference between objects and arrays in PHP>=5: arrays are by value while objects are by reference.

<?
$o = mysqli_fetch_object($res);
$o1 = $o;
$o1->value = 10;

$a = mysqli_fetch_array($res);
$a1 = $a;
$a1['value'] = 10;

echo $o->value; // 10
echo $a['value']; // (original value from db)
?>

Should same behaviour be intended, the object needs to be cloned:

<?
$o1 = clone $o;
?>

More about object cloning:
http://php.net/manual/en/language.oop5.cloning.php
up
19
Driek
11 years ago
As indicated in the user comments of the mysql_fetch_object, it is important to realize that class fields get values assigned to them BEFORE the constructor is called.
For example;
<?php

class Employee
{
  private
$id;

  public function
__construct($id = 0)
  {
   
$this->id = $id;
  }
}

// some code for creating a database connection... i.e. mysqli object
....
$result = $con->query("select id, name from employees");
$anEmployee = $result->fetch_object("Employee");
?>
will result in the ID being 0 because it is overridden by the constructor. Therefore, it is useful to check if the class field is already set.
I.e.
<?php
class Employee
{
  private
$id;

  public function
__construct($id = 0)
  {
    if (!
$this->id)
    {
      
$this->id = $id
   
}
  }
}
?>
Also note that the fields which will be assigned by fetch_object are case sensitive. If your table has the field "ID", it will result in the class field $ID being set. A simple work-around is to use aliases. I.e. "SELECT *, ID as id FROM myTable"
I hope this helps some people.
up
13
neo22s at gmail dot com
7 years ago
Since 5.6.21 and PHP 7.0.6

mysqli_fetch_object() sets the properties of the object AFTER calling the object constructor. Not BEFORE as was in previous versions.

So behaviour has changed. Seems a bug but not sure if was done intentionally.

https://bugs.php.net/bug.php?id=72151
up
5
macole at paypal dot com
7 years ago
Note that if you supply a class that has a __set() magic method defined in it, that method will be called for any properties that are not defined in your class.  For example:

<?php

class SomeClass {
    private
$id;
    public
$partner_name;
    public function
__set( $name, $value ) {
        echo
"__set was called!  Name = $name\n";
       
$this->$name = $value;
    }
}

$db = new mysqli( 'localhost', 'Username', 'Password', 'DbName' );
$result = $db->query( 'SELECT id, partner_name, partner_type FROM submissions' );
$object = $result->fetch_object( 'SomeClass' );

?>

Produces the following output:

__set was called!  Name = partner_type
up
8
benpptung at tacol dot biz
14 years ago
I don't know why no one talk about this.
fetch_object is very powerful since you can instantiate an Object which has the methods you wanna have.

You can try like this..

<?php
class PowerfulVO extends AbstractWhatEver {

    public
$field1;
    private
$field2; // note : private is ok

   
public function method(){
      
// method in this class
   
}
}

    
$sql = "SELECT * FROM table ..."
    
$mysqli = new mysqli(........);
    
$result = $mysqli->query($sql);
    
$vo = $result->fetch_object('PowerfulVO');
?>

Note : if the field is not defined in the class, fetch_object will add this field for you as public.

The method is very powerful, especially if you want to use a VO design pattern or class mapping feature with Flex Remoting Object( Of course, you need to have ZendAMF or AMFPHP ..framework)

Hope this help and open new possibilities for you
up
1
fedge-no at hotmail dot calm
7 years ago
I checked the bug database and as long as your PHP installation is up to date, the order of setting properties and calling the constructor should now follow the order specified in the documentation. There was a little while that a patch had been introduced where it was happening the other way around but that has been fixed now.
up
-1
Alex
12 years ago
Make sure to specify the full namespace for the "string $class_name" parameter and not a partial one, as it won't find it. For example:

<?php

namespace Root(backslash)FirstLevel
{
    public static function
Test($result)
    {
        return
mysqli_fetch_object($result, 'SecondLevel\\MyClass');
    }
}

?>

... will not work but this will:

<?php

namespace Root(backslash)FirstLevel
{
    public static function
Test($result)
    {
        return
mysqli_fetch_object($result, 'Root\\FirstLevel\\SecondLevel\\MyClass');
    }
}

?>
up
-5
me at philkershaw dot me
9 years ago
As a best practice, if you intend to use a defined class when using fetching_object(). Put the data obtaining code within a static method of the defined class. Otherwise, wherever you include the file (if not using an autoloader) the data connection will occur whether you want it to or not.

For example:

<?php

class User
{
    public
$name;

    public static function
getUser($id)
    {
       
$conn = new mysqli('localhost', 'username', 'password', 'database');
        if (
$result = $conn->query("SELECT * FROM users WHERE id = {$id} LIMIT 1")) {
            return
$result->fetch_object('User');
           
$result->close();
        }
    }
}
?>

Call the static method to obtain an instance of the User class with your data applied to it.

<?php
$user
= User::getUser('31');
echo
$user->name; // echo's 'Phil'
?>
up
-6
peterbelm at g[oogle]mail dot com
15 years ago
If your SQL code selects columns with empty names like so:

SELECT id as ``...

You will get a fatal error "Cannot access empty property", this took me a while to track down!

Obviously your SQL really shouldn't do that, and should be fixed but I'm going to submit a feature request to ask for a better error message for that.
To Top