I have code similar to the following:
class ModuleRaceRegistration extends Module
{
protected $strTemplate = "template";
protected function compile()
{
// this doesn't work
$this->strTemplate = "template2";
}
}
From within the compile function I need to change the $strTemplate member. How can I do this?
Is an error being returned? Also, this might not be the case but compile is a protected method so you can only call it from within the class. If you are trying to call it from outside of the class, then it would need to be public.
Let me try
Example from manual
<?php
abstract class Base {
abstract protected function _test();
}
class Bar extends Base {
protected function _test() { }
public function TestFoo() {
$c = new Foo();
$c->_test();
}
}
class Foo extends Base {
protected function _test() {
echo 'Foo';
}
}
$bar = new Bar();
$bar->TestFoo(); // result: Foo
?>
Related
I have a code structure like this:
class myclass{
use App/classes/Log
public function myfunc1 () {
$log_obj = new Log;
$log_obj->log('something1');
}
public function myfunc2 () {
$log_obj = new Log;
$log_obj->log('something2');
}
public function myfunc3 () {
$log_obj = new Log;
$log_obj->log('something3');
}
}
In reality, I have 12 methods which I need to make a object of Log class in the most of them. Now I want to know, isn't there any better approach to I do that (making an object) once? For example using a static property and setting the object to it or whatever ..
You can assign the Log instance to a property of your myclass using __construct. Here's an example of accessing a method of a class inside another class:
class Test {
public $var = 'test';
public function show_var() {
echo $this->var;
}
}
class Test_2 {
protected $test;
public function __construct() {
$this->test = new Test;
}
public function show_test() {
$this->test->show_var();
}
}
$test_2 = new Test_2;
$test_2->show_test();
See here in action.
I have tried in yii frame work adding set function in CController and try to add property in controller's object but it gives error
Can i user base class's __set function to set property of a instance.
Class Base {
public function __set() {
$this->$name = $value;
}
}
Class SubClass1 extends Base{
}
Class SubClass2 extends Base {
}
I create instance of SubClass1 or SubClass2 and i want to add property dynamically. Is it possible.
yes you can unless the property is private
Yes you can place your magic function your your class structure. Magic functions normally calls even if you are not defining in class file.
So, if you not create __set() in your class file, it won't affect much. But, if you want to do some extra things while setting under object then it will be helpful.
Also, __set() function need two parameter, $name and $value. Please refer following url,
__set() magic function
Regards
You can indeed, the following will demonstrate:
<?php
class Foo
{
private $vars = array();
public function __set($name, $value)
{
echo "Setting $name: $value<br />";
$this->vars[$name] = $value;
}
public function __get($name)
{
echo "Getting $name<br />";
return isset($this->vars[$name]) ? $this->vars[$name] : null;
}
}
class Bar extends Foo {}
$bar = new Bar();
$bar->baz = 'baz';
echo $bar->baz;
Which will output:
Setting baz: baz
Getting baz
baz
class Base {
protected $data;
public function __construct() {
$this->someMethodBaseClass();
}
protected function someMethodBaseClass() {
$this->data = 123456;
}
}
class subclass1 extends Base{
public function __construct() {
parent::__construct();
}
public function getData() {
return $this->data;
}
}
I need to call a function someFunction() how do I refer to it when it is in the following class structures?
abstract class A
{
protected $session;
protected $model;
public function __construct()
{
$session = new classSession;
$model = new classModel;
}
}
class classModel
{
$this->session->someFunction();
}
I've tried using $this->session->someFunction() but it does not work!
Firstly, you need to put it within the context of a function - code cannot exist on its own within a class body. Secondly, for anything in classModel to access $session, classModel has to extend class A. You end up with something like this:
class classModel extends A
{
public function foo()
{
$this->session->someFunction();
}
}
So for $this->session->someFunction(); to execute, you'd do this:
$model = new classModel();
$model->foo();
Whats wrong with me OOP here.
I want to inherit from Class A
The return_output method will do something common so I don't want to write that in the inherited classes.
However when I do B->return_output() I want it to run the do_something method in Class B, but I see that it always runs the method from Class A.
Should I replace $this with something else?
class A {
private function do_something() {
// do something
}
public function return_output() {
$op = $this->do_something();
// add some wrappers to $op
return $op;
}
}
class B extends A {
private function do_something() {
// do something different
}
}
var newClass = new B;
echo B->return_output();
use protected and not private since you are running it inside of scope a and scope b can't access private scope a:
class A {
protected function do_something() {
echo('ado_something');
}
public function return_output() {
$op = $this->do_something();
// add some wrappers to $op
return $op;
}
}
class B extends A {
protected function do_something() {
echo('bdo_something');
}
}
$newClass = new B;
echo $newClass->return_output();
class A {
private $aa;
protected $bb = 'parent bb';
function __construct($arg) {
//do something..
}
private function parentmethod($arg2) {
//do something..
}
}
class B extends A {
function __construct($arg) {
parent::__construct($arg);
}
function childfunction() {
echo parent::$bb; //Fatal error: Undefined class constant 'bb'
}
}
$test = new B($some);
$test->childfunction();
Question:
How do I display parent variable in child?
expected result will echo 'parent bb'
echo $this->bb;
The variable is inherited and is not private, so it is a part of the current object.
Here is additional information in response to your request for more information about using parent:::
Use parent:: when you want add extra functionality to a method from the parent class. For example, imagine an Airplane class:
class Airplane {
private $pilot;
public function __construct( $pilot ) {
$this->pilot = $pilot;
}
}
Now suppose we want to create a new type of Airplane that also has a navigator. You can extend the __construct() method to add the new functionality, but still make use of the functionality offered by the parent:
class Bomber extends Airplane {
private $navigator;
public function __construct( $pilot, $navigator ) {
$this->navigator = $navigator;
parent::__construct( $pilot ); // Assigns $pilot to $this->pilot
}
}
In this way, you can follow the DRY principle of development but still provide all of the functionality you desire.
Just echo it since it's inherited
echo $this->bb;
With parent::$bb; you try to retrieve the static constant defined with the value of $bb.
Instead, do:
echo $this->bb;
Note: you don't need to call parent::_construct if B is the only class that calls it. Simply don't declare __construct in B class.
class A {
private $aa;
protected $bb = 'parent bb';
function __construct($arg) {
//do something..
}
private function parentmethod($arg2) {
//do something..
}
}
class B extends A {
function __construct($arg) {
parent::__construct($arg);
}
function childfunction() {
echo parent::$this->bb; //works by M
}
}
$test = new B($some);
$test->childfunction();`
$bb has now become the member of class B after extending class A.
So you access $bb like it's an attribute of class B.
class A {
private $aa;
protected $bb = 'parent bb';
function __construct($arg) {
//do something..
}
private function parentmethod($arg2) {
//do something..
}
}
class B extends A {
function __construct($arg) {
parent::__construct($arg);
}
function childfunction() {
echo $this->bb;
}
}
$test = new B($some);
$test->childfunction();
all the properties and methods of the parent class is inherited in the child class so theoretically you can access them in the child class but beware using the protected keyword in your class because it throws a fatal error when used in the child class.
as mentioned in php.net
The visibility of a property or method
can be defined by prefixing the
declaration with the keywords public,
protected or private. Class members
declared public can be accessed
everywhere. Members declared protected
can be accessed only within the class
itself and by inherited and parent
classes. Members declared as private
may only be accessed by the class that
defines the member.
PHP Accessing Parent Class Protected Variable & Methods
class A {
protected $bb = 'parent bb';
protected function sayHello(){
echo 'Say Hello';
}
}
class B extends A {
public function childfunction() {
echo $this->bb.'<br>';
echo $this->sayHello();
}
}
$test = new B();
$test->childfunction();
Through parent class contructor you can pass data to parent class from child class. Have a look below example for better understanding
<?php
class Student
{
public $name;
function __construct($name){
$this->name = $name;
}
}
class Test extends Student
{
public $age;
function __construct($name,$age){
$this->age = $age;
parent::__construct($name);
}
}
$obj = new Test("sajib khan" ,21);
echo $obj->name;
echo $obj->age;
?>
class A {
private $points = 100;
public function getPoints() {
return $this->points;
}
}
class B extends A {
protected $points = 70;
public function getPoints() {
return parent::getPoints();
}
}
$element = new B();
echo $element->getPoints();
change the visibility private or protected for test