本例中的PHP OOP方法[关闭]

Im working with php for about 4 years now, but i still havent really used an OOP approach on any of my own scripts. I would really like to use it though, because for waht i heard and what i understand it makes developing much easier. For example the following code, it is a simple mysql-select, getting categories and from the results i am building a form-element, a dropdown-menu, there are a few steps involved like fe sorting stuff with natcasesort() too. Atm i would redo the same procedure for countries, and i would write the same code again, only that categories would be replaced with country, as you can see:

$result1 = mysql_query("SELECT * from categories WHERE hidden = 0");

while ($row = mysql_fetch_array($result1)) { 
    $cat_names = explode(",",$row['title_mulilingual']);
    $categories[$row['uid']] = $cat_names[$lang_id];
}

natcasesort($categories);
foreach ($categories as $key => $value) {
    if ($key == $active_key) $selected = ' selected="selected"';
    else $item_selected = '';
    $select_fields['cat_id'] .= '<option'.$selected.' value="'.$key.'">'.$value.'</option>';
}   

$cat_select = '<select name="category" >'.$select_fields['cat_id'].'</select>';


// the following part is the same as the first one, it only handles countries instead of categories

$result2 = mysql_query("SELECT * from countries WHERE hidden = 0");

while ($row = mysql_fetch_array($result2)) { 
    $country_names = explode(",",$row['title_mulilingual']);
    $countries[$row['uid']] = $country_names[$lang_id];
}

natcasesort($countries);
foreach ($countries as $key => $value) {
    if ($key == $active_key) $item_selected = ' selected="selected"';
    else $selected = '';
    $select_fields['country_id'] .= '<option'.$selected.' value="'.$key.'">'.$value.'</option>';
}   

$country_select = '<select name="country" >'.$select_fields['country_id'].'</select>';

So in the code it obviously is not OOP. But im guessing, that i could do this much easier by using OOP, right? Could someone help me to understand OOP better, by making this example an OOP-example? Thanks in advance, Jayden

Could someone help me to understand OOP better, by making this example an OOP-example?

Hey you could easily port this into OOP with a framework like MVC.

_{(source: php-html.net)}

"Model–View–Controller (MVC) is a design pattern for computer user interfaces that divides an application into three areas of responsibility:

• the Model: the domain objects or data structures that represent the application's state.
• The View, which observes the state and generates output to the users.
• The Controller, which translates user input into operations on the model." (Wikipedia, 2012)

Some really good OOP frameworks already available.

• ash.MVC
• cake PHP
• Symfony

A good tutorial on how to create a Model View Control can be found here.

Controller

This retrieves the data and then sends it to the model to be processed.

 include_once("model/Model.php");

 class Controller {
 public $model; 

 public function __construct()
 {
      $this->model = new Model();
 } 

 public function invoke()
 {
      if (!isset($_GET['book']))
      {
           // no special book is requested, we'll show a list of all available books
           $books = $this->model->getBookList();
           include 'view/booklist.php';
      }
      else
      {
           // show the requested book
           $book = $this->model->getBook($_GET['book']);
           include 'view/viewbook.php';
      }
 }
 }

Model

It processes the data to be presented

include_once("model/Book.php");

class Model {
public function getBookList()
{
    // here goes some hardcoded values to simulate the database
    return array(
        "Jungle Book" => new Book("Jungle Book", "R. Kipling", "A classic book."),
        "Moonwalker" => new Book("Moonwalker", "J. Walker", ""),
        "PHP for Dummies" => new Book("PHP for Dummies", "Some Smart Guy", "")
    );
}

public function getBook($title)
{
    // we use the previous function to get all the books and then we return the requested one.
    // in a real life scenario this will be done through a db select command
    $allBooks = $this->getBookList();
    return $allBooks[$title];
}

}

class Book {
public $title;
public $author;
public $description;

public function __construct($title, $author, $description)
{
    $this->title = $title;
    $this->author = $author;
    $this->description = $description;
}
}

View

Presents the data.

<?php 

    echo 'Title:' . $book->title . '<br/>';
    echo 'Author:' . $book->author . '<br/>';
    echo 'Description:' . $book->description . '<br/>';

?>

from my experience I find its easier to do OOP using a framework than learning it from scratch in web applications.

Theres also a good tutorial on creating your own framework at nettuts that can be found here, If you don't understand the above information this tutorial isn't to overwhelming.