How to access a variable with random value inside a class? - php

class Session{
protected $git = md5(rand(1,6));
public function __construct($config = array())
{
//// some code
$ses_id = $this->git;
}
public function _start_session()
{
//code again..
}
}
Here I can't assign a random value like this to variable called git. How can I do this if it is possible?
That random value need to be first time generated value only till the time it converts to Null.

Perform random inside your constructor,
class Session{
protected $git;
public function __construct($config = array())
{
//// some code
$this->git = md5(rand(1,6));
$ses_id = $this->git;
}
public function _start_session()
{
//code again..
}
}

Try setting the value of your variable in your constructor.
constructor will run every time you create an instance of your class.
try this code:
class Session{
protected $git;
public function __construct($config = array())
{
//// some code
$this->git = md5(rand(1,6));
}
public function _start_session()
{
//code again..
}
}
:)

Declare a variable inside a class,initialize the variables in class inside a constructor, which sets the variables once the object for that class is declared anywhere in the code.
I updated this answer if you want to do not change your session variable on each constructor call then use the below procedure.
class Session{
protected $git;
public function __construct($config = array())
{
$this->git = md5(rand(1,6));
if(!isset($_SESSION['ses_id']))
{
$_SESSION['ses_id'] = $this->git;
}
}
public function _start_session()
{
//code again..
}
}
I hope this helps you.

Try this using a global variable to track the random number:
class Session{
protected $git;
public function __construct($config = array())
{
//// some code
if (!isset($GLOBALS['random_val'])) {
$GLOBALS['random_val'] = md5(rand(1,6));
}
$this->git = $GLOBALS['random_val'];
$ses_id = $this->git;
var_dump("Session ID: ".$ses_id);
}
public function _start_session()
{
//code again..
}
}
$ses1 = new Session(); // Outputs string(44) "Session ID: 1679091c5a880faf6fb5e6087eb1b2dc"
$ses2 = new Session(); // Outputs string(44) "Session ID: 1679091c5a880faf6fb5e6087eb1b2dc"

Related

How to access global variable from inside class's function

I have file init.php:
<?php
require_once 'config.php';
init::load();
?>
with config.php:
<?php
$config = array('db'=>'abc','host'=>'xxx.xxx.xxx.xxxx',);
?>
A class with name something.php:
<?php
class something{
public function __contruct(){}
public function doIt(){
global $config;
var_dump($config); // NULL
}
}
?>
Why is it null?
In php.net, they told me that I can access but in reality is not .
I tried but have no idea.
I am using php 5.5.9.
The variable $config in config.php is not global.
To make it a global variable, which i do NOT suggest you have to write the magic word global in front of it.
I would suggest you to read superglobal variables.
And a little bit of variable scopes.
What I would suggest is to make a class which handles you this.
That should look something like
class Config
{
static $config = array ('something' => 1);
static function get($name, $default = null)
{
if (isset (self::$config[$name])) {
return self::$config[$name];
} else {
return $default;
}
}
}
Config::get('something'); // returns 1;
Use Singleton Pattern like this
<?php
class Configs {
protected static $_instance;
private $configs =[];
private function __construct() {
}
public static function getInstance() {
if (self::$_instance === null) {
self::$_instance = new self;
}
return self::$_instance;
}
private function __clone() {
}
private function __wakeup() {
}
public function setConfigs($configs){
$this->configs = $configs;
}
public function getConfigs(){
return $this->configs;
}
}
Configs::getInstance()->setConfigs(['db'=>'abc','host'=>'xxx.xxx.xxx.xxxx']);
class Something{
public function __contruct(){}
public function doIt(){
return Configs::getInstance()->getConfigs();
}
}
var_dump((new Something)->doIt());
Include the file like this:
include("config.php");
class something{ ..
and print the array as var_dump($config); no need of global.
Change your class a bit to pass a variable on the constructor.
<?php
class something{
private $config;
public function __contruct($config){
$this->config = $config;
}
public function doIt(){
var_dump($this->config); // NULL
}
}
?>
Then, if you
include config.php
include yourClassFile.php
and do,
<?php
$my_class = new something($config);
$my_class->doIt();
?>
It should work.
Note: It is always good not to use Globals (in a place where we could avoid them)

PHP how set default value to a variable in the class?

class A{
public $name;
public function __construct() {
$this->name = 'first';
}
public function test1(){
if(!empty($_POST["name"]))
{
$name = 'second';
}
echo $name;
}
$f = new A;
$f->test1();
Why don't we get first and how set right default value variable $name only for class A?
I would be grateful for any help.
You can use a constructor to set the initial values (or pretty much do anything for that matter) as you need to like this:
class example
{
public $name;
public function __construct()
{
$this->name="first";
}
}
Then you can use these default values in your other functions.
class example
{
public $name;
public function __construct()
{
$this->name="first";
}
public function test1($inputName)
{
if(!empty($inputName))
{
$this->name=$inputName;
}
echo "The name is ".$this->name."\r\n";
}
}
$ex=new example();
$ex->test1(" "); // prints first.
$ex->test1("Bobby"); // prints Bobby
$ex->test1($_POST["name"]); // works as you expected it to.
you have two options to set the default values for the class attributes:
Option 1: set at the parameter level.
class A
{
public $name = "first";
public function test1()
{
echo $this->name;
}
}
$f = new A();
$f->test1();
Option 2: the magic method __construct() always being executed each time that you create a new instance.
class A
{
public $name;
public function __construct()
{
$this->name = 'first';
}
public function test1()
{
echo $this->name;
}
}
$f = new A();
$f->test1();
Use isset() to assign a default to a variable that may already have a value:
if (! isset($cars)) {
$cars = $default_cars;
}
Use the ternary (a ? b : c) operator to give a new variable a (possibly default) value:
$cars = isset($_GET['cars']) ? $_GET['cars'] : $default_cars;

CodeIgniter use a global session variable from contructor

I need to use a session information in various functions of my controller, but I can't initialize it in the constructor, because I get an error. Message: Undefined property: Soporte::$session
class Soporte extends MY_Controller {
function __construct(){
parent::__construct( $module, $functionality );
}
public function actualizarSolicitud( $id_solicitud ){
$session_data = $this->session->userdata('session_user');
$user = $session_data['usuario'];
...
}
public function adminHistorico(){
$session_data = $this->session->userdata('session_user');
$user = $session_data['usuario'];
$config = array();
...
}
...
}
There's a way to initialize a global variable $user?
Try like below, model is quite complicated so I'm not providing it's code, but you should get the point. Any questions let me know.
/**
* This class is used for performing all read/write session operations
* Native php session is utilized (MY_Session library)
*/
class SessionManager extends BaseLibrary {
private $oUser;
public function __construct() {
parent::__construct();
$this->CI->load->model('User');
}
public function setUser(User $oUser) {
$this->CI->session->set_userdata('userId', $oUser->getId());
}
public function getUser() {
if ($this->oUser === null) {
$this->oUser = new User();
if ($this->CI->session->userdata('userId')) {
$this->oUser->setId($this->CI->session->userdata('userId'));
}
}
return $this->oUser;
}
public function logout() {
$this->CI->session->set_userdata('userId', NULL);
}
}

how to use objects created within the parent class in the child class PHP

I have this code and i´m trying to use a object
<?php
class Controller {
public $_view;
public function __construct() {
$this->_view = new View();
return $this->_view;
}
}
class View {
public $_params = array ();
public function set_params($index_name,$valores) {
$this->_params[$index_name] = $valores;
}
public function get_param($index_name){
return $this->_params[$index_name];
}
}
?>
i would like to do this:
class Index extends Controller {
public function index() {
$model = Model::get_estancia();
$usuarios = $model->query("SELECT * FROM usuarios");
$this->_view->set_params(); // cant be used.
$this->load_view("index/index");
}
}
i would like to use the set_parms function.
but i can't see the View Function, then i can not use.
Can someone explain and advise me a good and safe way?
Correction from Phil: If a __construct() method isn't found, PHP will revert to legacy constructor syntax and check for a method with the same name as the object. In your case the method index() is being treated as the constructor, and is preventing the parent's constructor from loading the view object into the $_view property.
You can force a class to inherit a parent's constructor by defining __construct() in the child and calling the parent's constructor:
public function __construct() {
parent::_construct();
}
Here is the fixed code:
<?php
class Controller {
public $_view;
public function __construct() {
$this->_view = new View();
return $this->_view;
}
}
.
class View {
public $_params = array ();
public function set_params($index_name,$valores) {
$this->_params[$index_name] = $valores;
}
public function get_param($index_name){
return $this->_params[$index_name];
}
}
.
class Index extends Controller {
public function __construct() {
parent::__construct();
}
public function index() {
$model = Model::get_estancia();
$usuarios = $model->query("SELECT * FROM usuarios");
$this->_view->set_params(); // cant be used.
$this->load_view("index/index");
}
}

How to pass php variable into a class function?

I want to pass php variable $aa into a class function. I have read some articles
in php.net, but I still don't understand well. Can anyone help me put the variable into this class? thanks.
$aa='some word';
class Action {
private $_objXML;
private $_arrMessages = array();
public function __construct() {
$this->_objXML = simplexml_load_file($aa.'.xml');
}
}
Simply put the variable names in the constructor.
Take a look at the snippet below:
public function __construct( $aa )
{
// some content here
}
I'm not sure what you mean... do you mean you want to access $aa in a function? If so:
$aa='some word';
class Action {
private $_objXML;
private $_arrMessages = array();
public function __construct() {
global $aa;
$this->_objXML = simplexml_load_file($aa.'.xml');
}
}
Or, on a per instance basis, you can do things like:
$aa='some word';
class Action {
private $_objXML;
private $_arrMessages = array();
public function __construct($aa) {
$this->_objXML = simplexml_load_file($aa.'.xml');
}
}
new Action($aa);
$aa='some word';
class Action {
private $_objXML;
private $_arrMessages = array();
public function __construct($aa) {
$this->_objXML = simplexml_load_file($aa.'.xml');
}
}
And use it like this:
$instance = new Action('something');
I don't know php, but my logic and google say this:
class Action {
private $_objXML;
private $_arrMessages = array();
public function __construct($aa) {
$this->_objXML = simplexml_load_file($aa.'.xml');
}
}
$object = new Action('some word');
This is simply called pass a variable as parameter of a function, in this case the function is the constructor of Action

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