php code to a class? [closed] - php

Question

Closed. This question needs to be more focused. It is not currently accepting answers.
Want to improve this question? Update the question so it focuses on one problem only by editing this post.
Closed 8 years ago.
Improve this question
How can I put those two code snippets in a class so the databasehandling is in a class? Like a PDO connection or put all that have to do with database is in a class, how would you guys do it?
Here are two parts of the code from different files. I am trying to develop a blog application.
<?php
mysql_connect("localhost", "root", "")or die(mysql_error());
mysql_select_db("blogg1")or die(mysql_error());
if(isset($_POST["submit"])){
$title = $_POST["title"];
$category = $_POST["category"];
$content = $_POST ["content"];
mysql_query("INSERT INTO blogdata(title , category , content) VALUES('$title', '$category', '$content')");
}else{
?>
<?php
mysql_connect("localhost", "root", "")or die(mysql_error());
mysql_select_db("blogg1")or die(mysql_error());
$sql = mysql_query("SELECT * FROM blogdata ORDER BY id DESC")or die(mysql_error());;
while($row = mysql_fetch_array($sql)){
$title = $row["title"];
$category = $row["category"];
$content = $row["content"];
?>
<table border = "1">
<tr><td><?php echo $title; ?></td><td><?php echo $category; ?></td></tr>
<tr><td colspan="2"><?php echo $content; ?></td></tr>
</table>
<?php
}
?>

Answer 1

First, you should keep your database credentials in a separate PHP file in a folder not accessible by the web, for example ~/lib/db.php
<?php
define('SQL_HOST', 'localhost');
define('SQL_DATABASE', 'your-db-name');
define('SQL_USER', 'your-db-user');
define('SQL_PASS', 'your-db-password');
?>
Then your Database class (also in ~/lib):
<?php
require_once('~/lib/db.php');
require_once('~/lib/BlogData.php');
class Database
{
protected $db = null;
function __construct()
{
// db connection options
$driverOptions = array(
PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES 'utf8'",
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_OBJ,
PDO::ATTR_EMULATE_PREPARES => false
);
// set new connection
$this->db = PDO(
"mysql:dbname=".SQL_DATABASE.";host=".SQL_HOST,
SQL_USER, SQL_PASS, $driverOptions
);
}
// This function lets you fetch blog data using any sort order you'd like and any WHERE criteria you want
function getBlogData($where = "1", $orderBy = "id DESC")
{
$stmt = $this->db->prepare("
SELECT *
FROM {'blogdata'} WHERE $where
ORDER BY $orderBy
");
$blogData = Array();
if ($stmt->execute())
{
while ($row = $stmt->fetch(PDO::FETCH_ASSOC)) {
$oneBlogData = new BlogData($this);
$oneBlogData->init($row);
$blogData[] = $oneBlogData;
}
}
return $blogData;
}
function insertBlogData(BlogData $blogData)
{
$stmt = $this->db->prepare("
INSERT INTO {'blogdata'} (title , category , content) VALUES
(:title, :category, :content);
");
$stmt->bindParam(':title', $blogData->title, PDO::PARAM_STR);
$stmt->bindParam(':category', $blogData->category, PDO::PARAM_STR);
$stmt->bindParam(':content', $blogData->content, PDO::PARAM_STR);
$stmt->execute();
}
}
?>
Then I would define another class for your blog data:
<?php
class BlogData {
public $title;
public $category;
public $content;
private $db;
function __construct(Database $db)
{
$this->db = $db;
}
function init($dbRow)
{
$this->title = $dbRow['title'];
$this->category = $dbRow['category'];
$this->content = $dbRow['content'];
}
function save()
{
// TODO: Write sql statement to save the row...
}
}
?>
Then your first block of code could create a new BlogData entry like this:
<?php
require_once('~/lib/Database.php');
$db = new Database();
if(isset($_POST["submit"]))
{
$blogData = new BlogData($db);
$blogData->title = $_POST["title"];
$blogData->category = $_POST["category"];
$blogData->content = $_POST["content"];
$db->insertBlogData($blogData);
}
?>
And your second block of code could look like this:
<?php
require_once('~/lib/Database.php');
$db = new Database();
$blogDataArray = $db->getBlogData("1", "id DESC");
echo "<table border = '1'>";
foreach($blogDataArray as $blogData)
{
echo "<tr><td>" . $blogData->title . "</td><td>" . $blogData->category . "</td></tr>";
echo "<tr><td colspan='2'>" . $blogData->content . "</td></tr>";
}
echo "</table>";
?>
This also makes it really easy to modify BlogData entries - just fetch the blog data from the Database using the getBlogData function, modify the object by simply changing it's values and calling save. For example:
<?php
// ...
$newContent = "New Content";
$blogData = $db->getBlogData("id='1'");
$blogData->content = $newContent;
$blogData->save();
?>
I should also point out the obvious that you need some unique field for your blog data entries. With some id, it'd be easier to write addToDatabase and save in one function.

Answer 2

Please see below for the code example:
class SomeClass {
protected $db = null;
protected $table = 'blogdata';
public function __construct()
{
// db connection options
$driverOptions = array(
PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES 'utf8'",
PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_OBJ,
);
// set new connection
$this->db = PDO(
"mysql:dbname=blogg1;host=localhost",
'root', '', $driverOptions
);
}
public function save($data)
{
// prepare your data
$title = $data["title"];
$category = $data["category"];
$content = $data ["content"];
// prepare statement
$stmt = $this->db->prepare("
INSERT INTO {$this->table} (title , category , content) VALUES
(:title, :category, :content);
");
$stmt->bindParam(':title', $title, PDO::PARAM_STR);
$stmt->bindParam(':category', $category, PDO::PARAM_STR);
$stmt->bindParam(':content', $content, PDO::PARAM_STR);
$stmt->execute();
}
public function getRecords()
{
$stmt = $this->db->prepare("
SELECT *
FROM {$this->table}
ORDER BY id DESC
");
$stmt->execute();
return $stmt->fetchAll();
}
}
And a usage example:
<?php
require_once('SomeClass.php');
$ent = new SomeClass();
if (isset($_POST["submit"])) {
$ent->save($_POST);
}
else {
// get and output
$records = $ent->getRecords();
if (count($records) > 0) {
?>
<table>
<?php
foreach ($records as $record) {
echo "<tr><td>{$record->title}</td><td>{$record->category}</td></tr>
<tr><td colspan='2'>{$record->content}</td></tr>";
}
?>
</table>