Introduction
This article explains the Strategy Pattern in PHP. One of the common issues we encounter while programming, is that must create decisions on completely different methods. Strategy Patterns have a common pattern that helps us to create decisions on completely different cases, more simply. To know this is good, let us use the scenario where you are developing a notification program. This notification program can check the given choices for a user. A user might want to be notified in many ways, like email, SMS, or Fax. Your program should check the available choices to contact that user and so create a call upon that. This case will simply be solved by the Strategy Pattern.
![Strategy pattern]()
Example
First of all, I will create an interface.
<?php
//interface.confirmation.php
interface confirmation
{
//method name confirm
public function Confirm();
}
?>
Let's create a "class.Emailconfirmation.php" file.
<?php
//include interface.confirm.php
include_once("interface.confirm.php");
//create class Emailconfirmation
class EmailConfirmation implements confirmation
{
//method name confirm
public function confirm()
{
//do something to confirm the user by Email
}
}
?>
And next I will create a "class.faxconfirmation.php" file.
<?php
//include class.emailconfirmation.php
include_once("class.emailconfirmation.php");
//implements confirmation interface
class FaxConfirmation implements confirmation
{
// create method confimation
public function confirm()
{
//do something to confirm the user by Fax
}
}
?>
And next I will create a "class.SMSconfirmation.php" file.
<?php
//include class.faxconfirmation.php
include_once("class.faxconfirmation.php");
//implements confirmation interface
class SMSConfirmation implements confirmation
{
public function confirm()
{
//do something to confirm the user by SMS
}
}
?>
Now I will use this code:
<?php
//include three files
include_once("class.Emailconfirmation.php");
include_once("class.Faxconfirmation.php");
include_once("class.SMSconfirmation.php");
//user object
$user = new User();
$confirmation = $user->getconfirmation();
switch ($confirmation)
{
case "email":
//object of Emailconfirmation class
$objconfirmation = new Emailconfirmation();
break;
case "sms":
//object of SMSconfirmation class
$objconfirmation = new SMSconfirmation();
break;
case "fax":
//object of Faxconfirmation class
$objconfirmation = new Faxconfirmation();
break;
}
$objconfirmation->confirm();
?>
In the code above I have used three classes known as "SMSconfirmation", "Emailconfirmation", and "Faxconfirmation". Of these classes implement the confirmation interface, that includes a method named notify. Every one of those categories implement that method on their own.