class io_dz {
/**
* Compress
*/
public static function Set($Data) {
if ($Data) {
$Out = addslashes(gzcompress(serialize($Data), 9));
} else {
$Out = FALSE;
}
return $Out;
}
/**
* Decompress
*/
public static function Get($Data) {
if ($Data) {
$Out = unserialize(gzuncompress(stripslashes($Data)));
} else {
$Out = FALSE;
}
return $Out;
}
}
it's a simple compress before serialize function. How would I call this function and use it on $data
I currently have:
$dataCompressor = new $io_dz();
$cdata = $dataCompressor->Set($data);
But it doesn't seem to work, any help would be appreciated!
Thank you!
You declared the method as static, you don't need to instanciate the object to access them.
Try only:
$cdata = io_dz::Set($data);
If you need more information about static method/attribute, you can check the PHP Manual that has quite a few easy to understand examples: http://php.net/manual/en/language.oop5.static.php
$cdata = $dataCompressor::Set($data);
You need :: because you made them static. If they weren't static and were only public functions it would be ->
Related
Here is my php code, the test method not giving wanted output, and the other weird thing is var_dump('a') print 3 times;
my wanted output is array('qtggccc','qtff23sdf');
public function main()
{
$serverIds = array('ff23sdf','ggccc');
$res = $this->test($serverIds);
var_dump($res);
}
public function test($serverIds,$imgArray = array())
{
if(count($serverIds) > 0){
$media_id = array_pop($serverIds);
$imgUrl= $this->hh($media_id);
array_push($imgArray,$imgUrl);
var_dump($serverIds);
var_dump($imgArray);
$this->test($serverIds,$imgArray);
}
var_dump('a');
return $imgArray;
}
public function hh($m)
{
return 'qt'.$m;
}
Try this:
class MyClass{
private $imgArray = array();
public function main(){
$serverIds = array('ff23sdf','ggccc');
$res = $this->test($serverIds);
print_r($this->imgArray);
}
public function test($serverIds){
if(count($serverIds) > 0){
$media_id = end($serverIds);
$imgUrl= $this->hh($media_id);
array_push($this->imgArray,$imgUrl);
//remove last element
array_pop($serverIds);
$this->test($serverIds);
}
return;
}
public function hh($m){
return 'qt'.$m;
}
}
$obj = new MyClass();
echo '<pre>';
$obj->main();
Why use recursion? You are using a complicated solution for a simple problem.
public function main()
{
$serverIds = array('ff23sdf','ggccc');
$res = array();
//These three lines replace an entire recursive function, making the code easier and saving a chunk of memory once you start using real arrays
foreach ($serverIds as $media_id){
array_unshift($res, $this->hh($media_id));
}
var_dump($res);
}
public function hh($m)
{
return 'qt'.$m;
}
Maybe I'm wrong to expressed it in the title, but I just do not understand how in the class like this.
<?php
class sample{
public $data = [];
public function pushIndex($index){
array_push($this->data, $index);
}
public function pushValue($value){
array_push($this->data["index"], $value);
// Some magic
}
public function forIndex($index){
return $this->data[$index];
// Some magic
}
}
To realize scheme like in Symfony, where will be spaghetti like this
<?php
$a = new sample;
$a->pushIndex("index")->pushValue("value");
$a->forIndex("index2")->pushValue("value2");
Maybe someone knows how to do it?
What you're talking about is called Fluent interface.
Returns the current object by using $this.
public function pushIndex($index){
array_push($this->a,$index);
return $this;
}
But what you want is to do something like this:
class sample
{
protected $a = [];
protected $currentIndex = null;
public function pushIndex($index)
{
$this->currentIndex = $index;
return $this;
}
public function pushValue($value)
{
if ($this->currentIndex === null) {
throw new LogicException('You need to call "pushIndex" or "forIndex" first.');
}
$this->a[$this->currentIndex] = $value;
return $this;
}
public function forIndex($index)
{
if (!isset($this->a[$index])) {
throw new RuntimeException(sprintf('Index "%s" doesn\'t exists', $index));
}
$this->currentIndex = $index;
return $this;
}
public function getArray()
{
return $this->a;
}
}
$a = new sample;
$a->pushIndex("index")->pushValue("value");
$a->forIndex("index2")->pushValue("value2"); // exception?
var_dump($a->getArray());
But what you want is pretty unclear.
I think what you're trying to achieve is something like this:
class sample{
public $a = [];
public $index = null;
public function pushIndex($index){
$this->index = $index;
$this->a[$index] = null;
return $this;
}
public function pushValue($value){
$this->a[$this->index] = $value;
return $this;
}
public function forIndex($index){
$this->index = $index;
return $this;
}
}
$a = new sample;
$a->pushIndex("index")->pushValue("value");
$a->forIndex("index2")->pushValue("value2");
echo "<pre>";
var_dump($a);
echo "</pre>";
This is called "method chaining". By returning a reference to the called object, you're able to perform further methods on the object, essentially "chaining" the methods.
I've had to adjust your code a little to get it the work I believe the way you want it to. It should provide a working example to help you understand method chaining.
I need to reconstruct head scripts and links so I would like to create a class that I can use for future references.
I started like :
class HeadClas{
public static $headprint;
function __construct(){
$this->headprint = "";
}
function addLinks(){
$this->headprint .= "addLinks";
return $this;
}
function addMeta(){
$this->headprint .= "addMeta";
return $this;
}
function printHead(){
return $this->headprint;
}
}
In the above case I would need to do
$print = new HeadClas;
$print->addLinks()->addMeta();
and I would like to do
$print = new HeadClas;
$print->printHead();
I did try
function printHead(){
return $this->addMeta()->addLinks();
}
But than I need to do
$print->printHead()->headprint;
What am I missing here?
Any help is appreciated!
Firstly, you should make the $headprint field non static. Making it static makes it the same reference for all future instances which will create undesirable results.
The printHead() should print the contents of that field like the method name suggests.
class HeadClass {
public $headprint;
function __construct() {
$this->headprint = "";
}
function addLinks() {
$this->headprint .= "addLinks";
return $this;
}
function addMeta() {
$this->headprint .= "addMeta";
return $this;
}
function printHead() {
$this->addLinks()->addMeta();
echo $this->headprint;
}
}
$printer = new HeadClass();
$printer->printHead();
I understand that one can use interfaces to mandate the definition of a function, but I cannot find something that enables one to mandate function calls, such that e.g. if I create a class being a member of another class (via extends, etc), with a function, for that class to automatically ensure that mandatory functions are called in part with that function.
I mean, to clarify further:
class domain {
function isEmpty($input) {
//apply conditional logic and results
}
}
class test extends domain {
function addTestToDBTable($test) {
/**
* try to add but this class automatically makes it so that all rules of
* class domain must be passed before it can run
* - so essentially, I am no longer required to call those tests for each and
* every method
**/
}
}
Apologies if this appears incoherent by any means. Sure, it seems lazy but I want to be able to force context without having to concern abou
Update:
Okay, to clarify further: in PHP, if I extend and declare a __construct() for a child class, that child class will override the parent __construct(). I do not want this, I want the parent construct to remain and mandate whatever as it pleases just as the child class may do so also.
I guess it can be done in two different ways.
Aspect Oriented Programming
Have a look here https://github.com/AOP-PHP/AOP
Generate or write Proxy classes
A really simple example could be:
<?php
class A {
public function callMe() {
echo __METHOD__ . "\n";
}
}
class B extends A {
// prevents instantiation
public function __construct() {
}
public function shouldCallMe() {
echo __METHOD__ . "\n";
}
public static function newInstance() {
return new ABProxy();
}
}
class ABProxy {
private $b;
public function __construct() {
$this->b = new B();
}
public function __call($method, $args) {
$this->b->callMe();
return call_user_func_array(array($this->b, $method), $args);
}
}
// make the call
$b = B::newInstance();
$b->shouldCallMe();
// Outputs
// ------------------
// A::callMe
// B::shouldCallMe
Hopes this helps a bit.
Sounds like you want a Decorator.
See This answer for a detailed explanation on how to do it. Note that it does not require a class extension.
I would use a domain-validating decorator with some doc-block metaprogramming magic. But this is really a job for an entire library, which no doubt exists.
fiddle
<?php
class FooDomain {
public static function is_not_empty($input) {
return !empty($input);
}
}
class Foo {
/**
* #domain FooDomain::is_not_empty my_string
*/
public function print_string($my_string) {
echo $my_string . PHP_EOL;
}
}
$foo = new DomainValidator(new Foo());
$foo->print_string('Hello, world!');
try {
$foo->print_string(''); // throws a DomainException
} catch (\DomainException $e) {
echo 'Could not print an empty string...' . PHP_EOL;
}
// ---
class DomainValidator {
const DOMAIN_TAG = '#domain';
private $object;
public function __construct($object) {
$this->object = $object;
}
public function __call($function, $arguments) {
if (!$this->verify_domain($function, $arguments)) {
throw new \DomainException('Bad domain!');
}
return call_user_func_array(
array($this->object, $function),
$arguments
);
}
public function __get($name) {
return $this->object->name;
}
public function __set($name, $value) {
$this->object->name = $value;
}
private function verify_domain($function, $arguments) {
// Get reference to method
$method = new \ReflectionMethod($this->object, $function);
$domains = $this->get_domains($method->getDocComment());
$arguments = $this->parse_arguments(
$method->getParameters(),
$arguments
);
foreach ($domains as $domain) {
if (!call_user_func(
$domain['name'],
$arguments[$domain['parameter']]
)) {
return false;
}
}
return true;
}
private function get_domains($doc_block) {
$lines = explode("\n", $doc_block);
$domains = array();
$domain_tag = DomainValidator::DOMAIN_TAG . ' ';
foreach ($lines as $line) {
$has_domain = stristr($line, $domain_tag) !== false;
if ($has_domain) {
$domain_info = explode($domain_tag, $line);
$domain_info = explode(' ', $domain_info[1]);
$domains[] = array(
'name' => $domain_info[0],
'parameter' => $domain_info[1],
);
}
}
return $domains;
}
private function parse_arguments($parameters, $values) {
$ret = array();
for ($i = 0, $size = sizeof($values); $i < $size; $i++) {
$ret[$parameters[$i]->name] = $values[$i];
}
return $ret;
}
}
Output:
Hello, world!
Could not print an empty string...
Already I extended and implemented from SPL iterator.
But if I want to use it, I should use it on a foreach.
I tried to use it in a while like this:
$news = new testClass();
while( $row = $news )
echo $row["name"];
It will create an infinite loop !
But with foreach, it works fine!
Here is top of my class:
class testClass implements \Iterator
Where is the mistake ?
Fist, bravo on using the SPL classes for this type of 'standard' problem. Too often have I seen inexperienced/sloppy developers (or even good ones that simply don't think ahead) reinvent the wheel in these types of situations.
You're missing some very important details about the implementation of the iterator interface.
see PHP:Iterator - Manual for more information, and the reference implementation from below.
First, you need to implement the, rewind, current, key, next, and valid functions. the reference implementation looks like this:
class myIterator implements Iterator {
private $position = 0;
private $array = array(
"firstelement",
"secondelement",
"lastelement",
);
public function __construct() {
$this->position = 0;
}
function rewind() {
var_dump(__METHOD__);
$this->position = 0;
}
function current() {
var_dump(__METHOD__);
return $this->array[$this->position];
}
function key() {
var_dump(__METHOD__);
return $this->position;
}
function next() {
var_dump(__METHOD__);
++$this->position;
}
function valid() {
var_dump(__METHOD__);
return isset($this->array[$this->position]);
}
}
)
And the code for traversing that implementation looks like this:
$it = new myIterator;
foreach($it as $key => $value) {
var_dump($key, $value);
echo "\n";
}
foreach is language construct that iterates through all elements. while executes block of code until given condition is true. To make it work you have to use your own function that checks for valid key and returns current element.
Finally I created a simple example of this:
<?php
/**
* #author Soroush Khosravi
* #copyright 2013
*/
class _Iterator
{
private $array;
public function setArray(array $data)
{
$this->array = $data;
}
public function reader()
{
if (is_null($this->array))
return false;
$elem = array_shift($this->array);
if (count ($this->array) > 0)
return $elem;
return false;
}
}
Class child extends _Iterator
{
function execute()
{
$this->setArray(array(1,2,3,4,5,6));
return $this;
}
}
$obj = new child;
$obj = $obj->execute();
while($row = $obj->reader())
echo $row;
?>