Using classes and objects together correctly? - php

Question

So had some great feedback, went back and read through a lot on OOP. So would you say this is correct? Where I've set variables in index.php you could use pdo to query the database to grab the user data and then say loop the objects?
index.php
<?php
// This is where you could query the db?
$firstname = "Vaughan";
$lastname = "Slater";
$age = 20;
// Create two new users
$user1 = new user($firstname, $lastname, $age); // From variables
$user2 = new user("Tom", "Jones", 41); // Static set
// Output new users & could you then loop this to pull a list of users from a query
echo print_r($user1, TRUE);
echo print_r($user2, TRUE);
?>
class.php
class user
{
private $_firstname;
private $_lastname;
private $_age;
public function __construct($firstname, $lastname, $age)
{
$this->_firstname = $firstname;
$this->_lastname = $lastname;
$this->_age = $age;
}
}
I think I'm making progress, just want to make sure I'm doing doing it wrong again.. It kind of reminds me of the relationship between things like html and css.

Answer 1

The basics are layed out, but now comes the complex part.
You'll have to query the DB. You'll get a collection to cycle over. For each item you get you'll have to copy the data into your objects and put them together into a collection (say, an array):
$users[] = new user($row['firstname'], $row['lastname'], $row['age']);
Note you can instruct with `pdo_mysql' to directly get objects instead of rows, so that copying will be done automatically.
Next, you'll cycle over that collection you have built and render it.
These passages are not necessary, you can directly render the database queries result.
This is a quick pointer to a wiki showing how to use pdo_mysql.
You'll have to do those passages if you want to stratify the application, which is a good (best?) practice.
This way, each cycle will be done in a different stratum and data is passed from one stratum to the next:
persistence (queries DB and populates $users[] array)
|
v
business (process data according to business logic)
|
v
presentation (render the results in HTML)
From top to bottom is the way data is passed trhough the strata.
Normally, though, the strata are shown in exactly the opposite way (bottom to top).