php define class within class (or next best thing) - php

Question

I am aware that a class cannot be defined within a class in php, however I'm curious if there's another way to achieve the desired effect.
I currently have a set of 3 objects used to conduct a search. The first is called $search_request. It contains properties like $keywords (string), $search_results_per_page (int), $page_requested (int), $owner_id (int)
I also have an object called $search_result, it contains properties like $total_matches (int), $result_set (array of objects)
Finally I have the $search_handler object which contains the $search_request and $search_result, along with functions that build the $search_result based on the $search_request.
Usage goes like so:
$search_handler = new search_handler();
$search_handler->search_request->keywords = "cats, dogs";
$search_handler->search_request->search_results_per_page = 10;
$search_handler->search_request->page_search_requested = 1;
$search_handler->get_search_result();
echo $search_handler->search_result->total_matches;
foreach($search_handler->search_result->result_set)
{
//do something
}
All of this works fine. The problem is I want to repeat this model for different objects, so currently I'm forced to use the hackey solution of the "search_" prefix on each class.
I'd like to have something like:
class search
{
public class request
{
$keywords = "";
$search_results_per_page = 5;
$page_requested = 1;
}
public class result
{
$total_matches = null;
$result_set = array();
}
public get_results()
{
//check cache first
$cached = look_in_cache(md5(serialize($this->request)));
if($cached)
{
$this->result->result_set = $cached;
$count = count($cached);
$this->result->total_matches = $count;
}
else
{
//look in db
$results = get_results_from_database($this->request->keywords); //db call goes here
$this->result->result_set = $results;
$count = count($results);
$this->result->total_matches = $count;
}
}
}
//usage
$search = new search();
$search->request->keywords = "cats, dogs";
$search->request->search_results_per_page = 10;
$search->request->page_search_requested = 1;
$search->get_results();
echo $search->results->total_matches;
foreach($search->results->result_set as $result)
{
//do something
}

Answer 1

If for whatever reason you don't want to have those classes you need in different files you can do the following
<?php
class search
{
var $request;
var $result;
public function __construct()
{
$this->request = new StdClass();
$this->request->keywords = "";
$this->request->search_results_per_page = 5;
$this->request->page_requested = 1;
$this->result = new StdClass();
$this->result->total_matches = null;
$this->result->result_set = array();
}
// ...
}
$search = new search();
var_dump($search->request, $search->result);
?>

Answer 2

There's several things to suggest here
First, if you're using PHP 5.3 or later, consider using namespaces and autoloading. That would allow you to make classes like \Cat\Search and \Dog\Search.
Second, I would avoid setting object properties directly. I would highly suggest you make your variables protected and use getters and setters instead. Limit your object interaction to methods and you can control the process much more easily.
$search_handler = new search_handler();
$search_handler->setKeywords(array("cats", "dogs"));

Answer 3

You could define your request and result classes as separately, and then have variables in your main class be assigned to instances of those.
Something like:
class result{
...
}
class request{
...
}
class search{
var results;
var request;
function __construct(){
$results = new ArrayObject();
$request = new stdClass();
}
...
}
Then you can assign/append to the list of results in your search function
and you can just assign a request object to your 'request' variable
$this->results[] = $newresult;
and loop through them when displaying