note 75412 modified in function.ArrayObject-offsetUnset by danbrown
| From: | danbrown@php.net | Date: | Fri, 28 Nov 2008 22:02:01 +0000 |
| Subject: | note 75412 modified in function.ArrayObject-offsetUnset by danbrown | ||
| References: | 1 | Groups: | php.notes |
| Request: | Send a blank email to php-notes+get-147294@lists.php.net to get a copy of this message | ||
Be careful when you are working with collections. This method works with the reference of an array
instead of its retrieved value.
So, you can do a mistake.
In order to understand have a look at code as follow:
<?php
class Employee
{
public function __construct()
{
}
}
class Company
{
private $arrEmployee;
public function __construct()
{
}
public function AddEmployee(Employee $oEmployee)
{
$this->arrEmployee[] = $oEmployee;
}
public function getEmployeeList()
{
return $this->arrEmployee;
}
}
?>
<?php
// first, creates the Company object
$oCompany = new Company();
// second, add 10 elements in
foreach( range(0, 9) as $index )
{
$oCompany->AddEmployee( new Employee() );
}
// get them
$arrEmployee = $oCompany->getEmployeeList();
// creates an ArrayObject from "$arrEmployee"
$arrayobject = new ArrayObject($arrEmployee);
// unsets its firt five elements
foreach( range(0, 4) as $index )
{
$arrayobject->offsetUnset($index);
}
// get them again
$arrEmployee = $oCompany->getEmployeeList();
// it shows just 5 elements, they were removed as reference via "offsetUnset" method
print_r($arrEmployee) ;
?>
--was--
Be careful when you are working with collections. This method works with the reference of an array
instead of its retrieved value.
So, you can do a mistake.
In order to understand have a look at code as follow:
<?php
class Employee
{
public function __construct()
{
}
}
class Company
{
private $arrEmployee;
public function __construct()
{
}
public function AddEmployee(Employee $oEmployee)
{
$this->arrEmployee[] = $oEmployee;
}
public function getEmployeeList()
{
return $this->arrEmployee;
}
}
?>
<?php
// first, creates the Company object
$oCompany = new Company();
// second, add 10 elements in
foreach( range(0, 9) as $index )
{
$oCompany->AddEmployee( new Employee() );
}
// get them
$arrEmployee = $oCompany->getEmployeeList();
// creates an ArrayObject from "$arrEmployee"
$arrayobject = new ArrayObject($arrEmployee);
// unsets its firt five elements
foreach( range(0, 4) as $index )
{
$arrayobject->offsetUnset($index);
}
// get them again
$arrEmployee = $oCompany->getEmployeeList();
// it shows just 5 elements, they were removed as reference via "offsetUnset" method
print_r($arrEmployee) ;
?>
http://php.net/manual/en/function.ArrayObject-offsetUnset.php