I work a lot in PHP but I never really understand the namespace method in PHP. Can somebody help me here? I have read on php.net's website its not explained good enough, and I can't find examples on it.
I need to know how I can make code in sample version.
namespace: sample
class: sample_class_1
function: test_func_1
class: sample_class_2
function: test_func_2
function: test_func_3
Like this?
<?php
namespace sample
{
class Sample_class_1
{
public function test_func_1($text)
{
echo $text;
}
}
class Sample_class_2
{
public static function test_func_2()
{
$c = new Sample_class_1();
$c->test_func_1("func 2<br />");
}
public static function test_func_3()
{
$c = new Sample_class_1();
$c->test_func_1("func 3<br />");
}
}
}
// Now entering the root namespace...
// (You only need to do this if you've already used a different
// namespace in the same file)
namespace
{
// Directly addressing a class
$c = new sample\Sample_class_1();
$c->test_func_1("Hello world<br />");
// Directly addressing a class's static methods
sample\Sample_class_2::test_func_2();
// Importing a class into the current namespace
use sample\Sample_class_2;
sample\Sample_class_2::test_func_3();
}
// Now entering yet another namespace
namespace sample2
{
// Directly addressing a class
$c = new sample\Sample_class_1();
$c->test_func_1("Hello world<br />");
// Directly addressing a class's static methods
sample\Sample_class_2::test_func_2();
// Importing a class into the current namespace
use sample\Sample_class_2;
sample\Sample_class_2::test_func_3();
}
If you're in another file you don't need to call namespace { to enter the root namespace. So imagine the code below is another file "ns2.php" while the original code was in "ns1.php":
// Include the other file
include("ns1.php");
// No "namespace" directive was used, so we're in the root namespace.
// Directly addressing a class
$c = new sample\Sample_class_1();
$c->test_func_1("Hello world<br />");
// Directly addressing a class's static methods
sample\Sample_class_2::test_func_2();
// Importing a class into the current namespace
use sample\Sample_class_2;
sample\Sample_class_2::test_func_3();
Related
I want to make a PHP class, lets say Myclass.php. Now inside that class I want to define just the class itself and some instance variables. But all the methods must come from a Myclass_methods.php file. Can I just include that file into the class body?
I have good reasons why I want to seperate this. In short, I'll have a backend in which I can change the business logic of a class, while all other things must remain untouched. The system maintains all the ORM and other stuff for me.
But if this is a bad idea, it might be better to re-generate the whole class file after editing the business logic (so, the user-defined methods in this case).
Performance question: If during one request Myclass.php is included just once, actually that Myclass_methods.php should also be included just once. Might be wrong. Experts?
No. You cannot include files in the class body.
In a file defining a class, you may only include files in a method body or outside the class body.
From your description I take you want this:
<?php // MyClass.php
class MyClass
{
protected $_prop;
include 'myclass-methods.php';
}
<?php // myclass-methods.php
public function myMethod()
{
$this->$_prop = 1;
}
Running this code will result in
Parse error: syntax error, unexpected T_INCLUDE, expecting T_FUNCTION
What is possible though is this
<?php // MyClass.php
class MyClass
{
protected $_prop;
public function __construct() // or any other method
{
include 'some-functions.php';
foo($b); // echoes 'a';
}
}
<?php // some-functions.php
$b = 'a';
function foo($str)
{
echo $str;
}
Doing it this way, will import the contents of the include file into the method scope, not the class scope. You may include functions and variables in the include file, but not methods. You could but should not put entire scripts into it as well and change what the method does, e.g.
<?php // MyClass.php
// ...
public function __construct($someCondition)
{
// No No Code here
include ($someCondition === 'whatever') ? 'whatever.php' : 'default.php';
}
// ...
<?php // whatever.php
echo 'whatever';
<?php // default.php
echo 'foo';
However, patching the class this way to exhibit different behavior is not how you should do it in OOP. It's just plain wrong and should make your eyes bleed.
Since you want to dynamically change behavior, extending the class is also not a good option (see below why). What you really will want to do is write an interface and make your class use objects implementing this interface, thus making sure the appropriate methods are available. This is called a Strategy Pattern and works like this:
<?php // Meowing.php
interface Meowing
{
public function meow();
}
Now you got the contract that all Meowing Behaviors must obey, namely having a meow method. Next define a Meowing Behavior:
<?php // RegularMeow.php
class RegularMeow implements Meowing
{
public function meow()
{
return 'meow';
}
}
Now to use it, use:
<?php // Cat.php
class Cat
{
protected $_meowing;
public function setMeowing(Meowing $meowing)
{
$this->_meowing = $meowing;
}
public function meow()
{
$this->_meowing->meow()
}
}
By adding the Meowing TypeHint to setMeowing, you make sure that the passed param implements the Meowing interface. Let's define another Meowing Behavior:
<?php // LolkatMeow.php
class LolkatMeow implements Meowing
{
public function meow()
{
return 'lolz xD';
}
}
Now, you can easily interchange behaviors like this:
<?php
require_once 'Meowing.php';
require_once 'RegularMeow.php';
require_once 'LolkatMeow.php';
require_once 'Cat.php';
$cat = new Cat;
$cat->setMeowing(new RegularMeow);
echo $cat->meow; // outputs 'meow';
// now to change the behavior
$cat->setMeowing(new LolkatMeow);
echo $cat->meow; // outputs 'lolz xD';
While you also could have solved the above with inheritance by defining an abstract BaseCat and meow method and then deriving concrete RegularCat and Lolkat classes from that, you have to consider what you want to achieve. If your cats will never change the way they meow, go ahead and use inheritance, but if your RegularCat and Lolkat is supposed to be able to do arbitrary meows, then use the Strategy pattern.
For more design patterns in PHP, check these resources:
http://www.php.net/manual/en/language.oop5.patterns.php
http://www.ibm.com/developerworks/library/os-php-designptrns/
http://www.fluffycat.com/PHP-Design-Patterns/
http://sourcemaking.com/design_patterns
Might it not be an idea to create the core class with the relevant base functionality and then extend this with the required methods - it seems like a more logical approach.
I'll start by saying I'm not too clear why this problem is not best solved using a base class containing the methods, subclasses containing the data, and dynamic class loading. I'll assume you have a good reason.
Once your provider supports PHP 5.4 you can do what you want using traits.
Code File:
if ($pet === 'dog') include 'dog.php';
elseif ($pet === 'cat') include 'cat.php';
else die('Unknown pet');
class Pet {
use PetSounds;
}
$myPet = new Pet();
$myPet->speak();
File cat.php
trait PetSounds {
function speak() { echo 'meow'; }
}
File dog.php
trait PetSounds {
function speak() { echo 'woof'; }
}
You could make this even cleaner by naming both include files the same, putting them in different subdirectories, and using set_include_path() or defining an __autoload() function to select between them. Like I said though, this same problem could be solved better using inheritance. If you have a multiple-inheritance type problem though, if for instance you have four kinds of pets with five kinds of colors with three hair types and you need a different combination of methods for each of the 60 different classes, this is the right solution.
5.4 is currently just a Release Candidate (as of 2/24/2012) and even once released most hosts will not support it for many months - mine took 18 months after 5.3 was released before they would support it. Until then you must write entirely separate and complete class files. You can however format your classes with an eventual change to traits in mind.
Right now you can partially get what you want using magic methods and have an easy upgrade to traits when they are available.
Code File:
if ($pet === 'dog') include 'dog.php';
elseif ($pet === 'cat') include 'cat.php';
else die('Unknown pet');
class Pet {
public function __call($name, array $arguments)
{
array_unshift($arguments, $this);
return call_user_func_array("TraitFunc_$name", $arguments);
}
}
$myPet = new Pet();
$myPet->speak();
File cat.php
function TraitFunc_speak(Pet $that) { echo 'meow'; }
File dog.php
function TraitFunc_speak(Pet $that) { echo 'woof'; }
You are limited however in that your functions can not access private and protected class properties and methods and you can not use this method to provide magic methods such as __get(). Traits will solve both of those limitations.
What about using traits for this? Would that be an acceptable option? This is something I am currently experimenting with and it seems to work quite while.
A simplified version of what I am doing is basically like this. I have an application with shared core files and multiple projects. Within those projects i have modules. I want to have functions that are available for the entire project on a core level but only for that specific project.
My project controller
if(is_file(PROJECT_PATH.'/project_extensions.trait.php')){
// additional functions for this specific project
require_once(PROJECT_PATH.'/project_extensions.trait.php');
}else{
// no additional functions
trait Extensions{};
}
Class Project{
USE Extensions;
// default functions shared between all projects
function shared_stuff(){
}
}
Extensions file
trait Extensions{
// project-specific extensions
function this_project_only(){
echo 'Project Only';
}
}
Module file in the project
class MyModule extends Modules{ // modules extends projects in a different class not relevant here
function do_something(){
echo $this->project_only();
}
}
Since PHP5.4 release you can create dynamic objects like this: https://github.com/ptrofimov/jslikeobject
But this is scarcely the best practice.
Reviving an old question but this is a fairly simple solution. Do you need the common function calls to be exclusive to your class? If not, simply include your common function file(s) within the same scope as your class. You will need to create methods in your class but they will only need to call the common function. Here's a simple SOAP server example:
<?php
include 'post_function.php';
$server = new SoapServer( null, array('uri' => "http://localhost/") );
$server->setClass( 'postsoapclass' );
$server->handle();
class postsoapclass
{
public function animalNoise( $animal )
{
return get_animal_noise($animal);
}
}
?>
post_function.php
<?php
function get_animal_noise($animal)
{
if(strtolower(trim($animal)) == 'pig')
{
return 'Oink';
}
else
{
return 'This animal is mute';
}
}
?>
I have had to do what you are describing in cases where I maintain a free version and a premium version of the same software. Because, as #Gordon noted, you cannot do exactly this:
class SomeClass {
premium_file = "premium.php";
if (file_exists($premium_file)) {
require($premium_file);
}
Instead I do this:
premium_file = "premium.php";
if (file_exists($premium_file)) {
require($premium_file);
}
class SomeClass {
...
For functions you want to reference, create class methods in the main class, and call the included file's method, passing the $this pointer as a parameter. So that I can tell at a glance where functions are, I will prefix the name of the included functions as shown below:
class SomeClass {
...
// Premium functions
public function showlist() {
premium_showlist($this);
}
You can include or require before declaring your class like below:
require 'path-to-file';
class myClass{
function show($uid){
}
}
The answer is yes, for example:
Into class construct, pass to the function (that's into the included file) values as params:
$this->wpd = $this->wpdopt = 'something';
include_once('/common/functions_common.php');
$this->wpdb = wpquery($sql='', $mode='', $this->wpd);
Into the included functions_common.php file:
function wpquery($sql, $mode, $wdp)
{
if(!empty($wdp))
{ return true; } else { return false; }
}
Into class methods:
$sql = "UPDATE ..... SET ... WHERE LOWER(user_email) = . ...";
$this->wpdb = wpquery($sql,'update',$this->wpd);
OR
$retval_var = $this->wpdb = wpquery($sql,'update',$this->wpd);
OR even
$this->var = $this->wpdb = wpquery($sql,'update',$this->wpd);
Cheers to all the lovely and cool people
I came across this recently, and came up with a solution, that helped in my case. I wanted many functions in a class, but the class became bloated, so wanted to separate out the class functions into groups for readability. It took a little time to accomplish, but since the functions of the class didn't rely (much) on $this, I removed "$this" from the class functions and created several helper files to include those functions. When $this was necessary, I could nevertheless move the function into a helper file, by passing $this to the function, adding public set/get functions where necessary. It's a hack, but it's sure to help someone
class myClass
{
var x;
function myClass()
{
$this->x = 0;
}
function myFunc1Group1()
{
$x = $this->x;
$x++;
$this->x = $x;
}
function myFunc2Group1(){}
function myFunc1Group2(){}
function myFunc2Group2(){}
}
can be worked around to
class myClass
{
var x;
function myClass()
{
$this->x = 0;
}
function doSomething()
{
// not called on $this but takes $this as a parameter
myFunc1Group1($this);
}
}
and helper function set 1
function myFunc1Group1($THIS_OBJECT)
{
$x = $THIS_OBJECT->getX();
$x++;
$THIS_OBJECT->setX($x);
}
function myFunc2Group1($THIS_OBJECT){}
and helper function set 2, etc.
Probably not the best route in all cases, but helped me out a lot. Basically the class functions were only to construct and delegate, and the calculations were put into helpers.
I'm trying to run this code on the same file:
namespace Foo1\Bar\SubBar;
class SubBarClass {
public function __construct() {
echo 'From Foo1';
}
}
namespace Foo2\Bar\SubBar;
class SubBarClass {
public function __construct() {
echo 'From Foo2';
}
}
use Foo1\Bar\SubBar;
$foo1 = new SubBarClass;
use Foo2\Bar\SubBar;
$foo2 = new SubBarClass;
The ideia is to change namespaces and echo the related value.
But it's returning the following error:
( ! ) Fatal error: Cannot use Foo2\Bar\SubBar as SubBar because the name is already in use in C:\wamp\www\xxx\namespaces.php on line 30
Line 30: use Foo2\Bar\SubBar;
How can I interchange namespaces on the same file?
Thks!
use keyword is used to import that namespace to be accessed in your current file scope. It does not act as a namespace "instance constructor".
You're current under Foo2\Bar\SubBar namespace. Like a directory of classes, while you're here, you should access other namespaces from the root (\):
$foo2 = new SubBarClass;
$foo1 = new \Foo1\Bar\SubBar\SubBarClass;
There is no need to use use for those namespaces (although you can, specially when they share parent namespaces), they are already declared in the same file you're using them.
For more information about this, consider reading the manual, where it describes using multiple namespaces in the same file.
This happens because the last defined namespace is the one currently active.
So, when I type:
use Foo1\Bar\SubBar;
I'm still on the last defined namespace: Foo2\Bar\SubBar.
Hence, when I type:
use Foo2\Bar\SubBar;
I'm trying to use the currently active namespace. That's why the Fatal error is returned.
On possible solution is:
namespace Foo1\Bar\SubBar;
class SubBarClass {
public function __construct() {
echo 'From Foo1';
}
}
namespace Foo2\Bar\SubBar;
class SubBarClass {
public function __construct() {
echo 'From Foo2';
}
}
use Foo1\Bar\SubBar;
$foo1 = new SubBar\SubBarClass;
echo '<br>';
$foo2 = new SubBarClass;
Cheers!
I created a common.php for my all the global function. When I run my first function {{Common::test()}}
It's working fine But I can not use model in it.
namespace App\library;
{
class Common {
public static function test()
{
echo "Yes";
return "This comes from Common File";
}
public static function getCmsBlocks()
{
$model = Modelname::all();
if($model){
echo "asdad";
}else
{
echo "sadasd";
}
}
}
}
I don't get my output when I run {{Common::getCmsBlocks()}}
If your model is in different namespace than App\library you will need to prefix the model class name with its namespace, otherwise PHP will try to load App\library\Modelname which might not be what you need.
Replace
$model = Modelname::all();
with
$model = \Your\Model\Namespace\Modelname::all();
If you use your Modelname class in multiple place in declared namespace, you can import/alias that using use statement so that you can refer to that class by classname in your code:
namespace App\library;
use Your\Model\Namespace\Modelname;
{
class Common {
public static function getCmsBlocks()
{
$model = Modelname::all(); //this will work now
}
}
}
There is no way to define global use to bused by all namespaces in your file, as use always refers to the namespace being declared.
As above the answer is perfect but just a few addition if you don't want to include namespace everytime on at start of each file
Use this :
\App\ModelName::all();
\App\ModelName1::update(item);
\App\ModelName2::find(1);
give path like above and there will be no need to use namespace everytime .
Note: above is path to model which is inside App directory . So change accordingly if you are keeping them at separate place .
In my php file i am doing it this way
pagecontroller.php
include_once(RUDRA."/controller/AbstractTemplateController.php");
if (file_exists(get_include_path() . CONTROLLER_PATH . "/TemplateController.php" )) {
include_once (CONTROLLER_PATH . "/TemplateController.php");
} else {
include_once (RUDRA . "/controller/TemplateController.php");
}
in TemplateController.php a class named 'TemplateController extends AbstractTemplateController' is defined, if a developer has already defined a class TemplateController which also extends AbstractTemplateController then it will use that otherwise it will fallback to default definition.
then in other files i will simply use something like this
include_once("pagecontroller.php")
$c = new TemplateController();
is there any better way to do this?
since I am including two files AbstractTemplateController.php & TemplateController.php in both cases, I cpuld have written both class definitions in same file which would have saved one include(if there is no custom TemplateController.php)?
I tried writing AbstractTemplateController & TemplateController in one single file but if then developer has defined his own TemplateController it creates two classes with same name situation.
pupose is to have atleast one definition to be there, if customDefinition does not exists then only use default one. and this code is to be abstract.
in the beginning if CustomClass exists (in a specific folder) then that the definition to be used, else use default one (which is nothing but simply extends AbstractOne)
CONTROLLER_PATH . "/TemplateController.php"
class TemplateController extends AbstractTemplateController {
/* over-ridden method of AbstractTemplateController
*/
public function invoke($abc,$def){
echo $abc . " " .$def;
}
}
RUDRA . "/controller/TemplateController.php"
class TemplateController extends AbstractTemplateController {
// nothing at all this is simply to make sure TemplateController class is available
// for others to use.
}
Use namespaces and convention.
E.g. you could check if there's a TemplateController-class present that extends the AbstractTemplateController that's different from your namespace (As your implementation will be specific for your namespace), if there isn't ; fall back to your implementation of the TemplateController.
http://php.net/manual/en/language.namespaces.php
php provides a function for not letting you load/write a class more then once.
bool class_exists ( string $class_name );
example is :
<?php
function __autoload($class)
{
include($crigger_error("Unable to load class: $class", E_USER_WARNING);
}
}
if (class_exists('MyClass')) {
$myclass = new MyClass();
}lass . '.php');
// Check to see whether the include declared the class
if (!class_exists($class, false)) {
trigger_error("Unable to load class: $class", E_USER_WARNING);
}
}
if (class_exists('MyClass')) {
$myclass = new MyClass();
}
?>
in above example autoload is used, you could do it without autoload this way :
<?php
// Check that the class exists before trying to use it
if (class_exists('MyClass')) {
$myclass = new MyClass();
}
?>
still i am saying you better get habit of using namespaces. they are awesome and work every where.
I posted some questions previously regarding the use of Namespaces in PHP and from what I got, this example code I have below should be working.
However I am getting errors when I try to use Namespace in PHP like this. Here is the first error when running the code below as is...
Fatal error: Class 'Controller' not found in E:\Controllers\testing.php on line 6
E:\Controller\testing.php File
<?php
use \Controller;
include('testcontroller.php');
$controller = new Controller;
$controller->show();
?>
E:\Controller\testcontroller.php File
<?php
use \Library\Registry;
namespace Controller
{
class Controller
{
public $registry;
function __construct()
{
include('E:\Library\Registry.class.php');
$this->registry = new Registry;
}
function show()
{
echo $this->registry;
echo '<br>Registry was ran inside testcontroller.php<br>';
}
}
}
?>
E:\Library\Registry.class.php File
<?php
namespace Library\Registry
{
class Registry
{
function __construct()
{
return 'Registry.class.php Constructor was ran';
}
}
}
?>
As you can see I tried to make it as simple as possible just to get the Namespace part working. I have tried different variations and cannot seem to figure it out.
Even when using use statement, you need to specify the namespace of the class you are trying to instantiate. There are a lot of examples here: http://www.php.net/manual/en/language.namespaces.importing.php
To understand it better, I will describe to you how it works. In your case, when you do use \Controller, the whole Controller namespace becomes available to you, but not the classes that are in this namespace. So, for example:
<?php
include('testcontroller.php');
use \Controller;
// Desired class is in namespace!
$controller = new Controller\Controller();
// Error, because in current scope there is no such class
$controller = new Controller();
$controller->show();
?>
Another example:
testcontoller.php:
<?php
namespace Some\Path\To\Controller;
class Controller
{
function __construct()
{
}
function show()
{
echo '<br>Was run inside testcontroller.php<br>';
}
}
?>
testing.php:
<?php
include('testcontroller.php');
use \Some\Path\To\Controller;
// We now can access Controller using only Controller namespace,
// not Some\Path\To\Controller
$controller = new Controller\Controller();
// Error, because, again, in current scope there is no such class
$controller = new Controller();
$controller->show();
?>
If you wish to import exactly the Controller class, you need to do use Controller\Controller - then this class will be accessible in your current scope.
Its not that good idea to name the namespace, like the class, because it is confusing (and I think this is what happens here). There moment you define the alias via use Controller this referenes to either a class \Controller, or the namespace \Controller, but your class, because it is within the namespace, is named \Controller\Controller 1
use Controller;
$class = new Controller\Controller;
or
$class = new \Controller\Controller;
or
use Controller\Controller;
$class = new Controller;
The idea is, that the moment you try to access a class with its relative name it tries to map the "first part" against any alias defined using use (remeber use MyClass is the same as use MyClass as MyClass. The thing after as is the alias).
namespace MyNamespace\MyPackage\SomeComponent\And\So\On {
class MyClass {}
}
namespace Another {
use MyNamespace\MyPackage\SomeComponent; // as SomeComponent
$class = new SomeComponent\An\So\On\MyClass;
}
As you can see PHP finds SomeComponent as the first part and maps it against the SomeComponent-alias the line above.
You can read more about it in the manual about namespaces.
1 Its called "Full-qualified classname", if you name a class with its complete name.
When you put a class Controller in the namespace Controller, then you have to reference it that way:
$controller = new Controller\Controller();
\Controller would be a class in the global (default) namespace, i.e. as if you used no namespace at all.
Strangely I have found that in my example code from the Question above, if I change all the Namespace's that are defined to something like MyLibrary so it would be like this code below...
E:\Library\Registry.class.php File
<?php
namespace MyLibrary
{
class Registry
{
function __construct()
{
echo 'Registry.class.php Constructor was ran';
}
}
}
?>
Then when I use use MyLibrary\Registry; in another file, I am able to access it how I had planned...
$this->registry = new Registry;
The reason this is very strange to me is this now makes a class name appear to be a Namespace as well. So I would not need to set a Namespace to 'MyLibrary\Library' to access the Registry instead I would do it like I showed in this answer to be able to access it with just calling the name of the class.
I hope this makes sense and helps someone else. I will not accept this as the answer as I am hoping someone with more know-how will come in and post a better Answer with explanation
try
<?php
use \Library\Registry;
namespace Controller;
class Controller
{
public $registry;
function __construct()
{
include('E:\Library\Registry.class.php');
$this->registry = new Registry;
}
function show()
{
echo $this->registry;
echo '<br>Registry was ran inside testcontroller.php<br>';
}
}
?>
and
<?php
namespace Library\Registry;
class Registry
{
function __construct()
{
return 'Registry.class.php Constructor was ran';
}
}
?>
First off, I believe you are using composer or composer is initialised in your project. If so, check composer.json file for your autoload, psr-4 definition. For example, if the root of your application is "App", then in your psr-4, you should be doing "autoload": { "psr-4": { "App\\": "./" } },
Furthermore, remember to clear composer cache and dump-autoload from the terminal as follows:
composer clear-cache
composer dump-autoload