[RESOLVED] php &amp; classes

[RESOLVED] php & classes

Fuzzylr

Ok, I'm trying to under classes and how they work and I'm following an example in a book but it seems I've got something wrong. Because it's not using any of my code. I'm rather confused. I have checked my php for errors. I don't see any. So since techincally there is enough code to display a table and I was wondering why stuff is not working? I've been checking it for 2 days now and can't seem to find the solution.

googling php classes hasn't been all that easy either.

index.php

<?php
require('body.inc');

$homepage = new Page();

$displaypage -> Display();
?>

body.inc

<?php

class Page
{
	// Class Page Attributes
	var $content;
	var $title = 'Registration';
	var $keywords = 'WoW, World of warcraft, private, server, mangos';

// Class Page's Operatoins
function SetContent($newcontent)
{
	$this->content = $newcontent;
}

function SetTitle($newtitle)
{
	$this->title = $newtitle;
}

function SetKeywords($newkeywords)
{
	$this->keywords = $newkeywords;
}

function Display()
{
	echo "<html>\n<head>\n";
	$this -> DisplayTitle();
	$this -> DisplayKeywords();

	echo "</head>\n<body>\n";

	echo "</body>\n</html>\n";
}

function DisplayTitle()
{
	echo '<title> $this->title </title>';
}

function Displaykeywords()
{
	echo "<META name=\"keywords\" content=\"$this->keywords\">";
}

function DisplayHeader()
{
?>
		<table align='center' width='50%'>
		<tr bgcolor = 'black'> <td> <h2> Registration </h2> <td> </tr>
		</table>
<?php
	}

}

?>

NogDog

In the first piece of code, since you named the instantiated object $homepage, that's the variable name to use to call the Display() method:

$homepage->Display();

PS: It probably should have thrown an error message, so while testing you might want to turn on all errors, either via your php config file or with:

<?php
ini_set('display_errors', 1);
error_reporting(E_ALL);
// rest of code...
?>

Fuzzylr

NogDog;10939247 wrote:
In the first piece of code, since you named the instantiated object $homepage, that's the variable name to use to call the Display() method:
$homepage->Display();
PS: It probably should have thrown an error message, so while testing you might want to turn on all errors, either via your php config file or with:
<?php
ini_set('display_errors', 1);
error_reporting(E_ALL);
// rest of code...
?>

Thank you sir. that worked. Don't ask me why I copied that wrong. Lesson learned.

nrg_alpha

Fuzzylr, given that you are declaring your object properties using the 'var' keyword, denotes PHP 4 OOP usage..Not sure which PHP version you are using (4 or 5), but you would be better off using PHP 5 (and version 5 notation) instead, as OOP has been greatly improved in that version.

Also, instead of stuffing your class into an include as you have done, another alternative could be to put your classes in a folder and then you can use an autoload() method to have PHP check which class(es) in your page is being instantiated, and have the system automatically load those classes for you..

So for example, assuming you save your classes with '.class.php' postfixing in a folder called classes set in the root of your site, you could do something like:

function __autoload($class) {
   require_once '/classes/'.$class . '.class.php';
}

That snippet would be in your main page.. so you can keep all your classes in that specific classes folder, and calling all classes you use is simple and automated (granted, if you are using PHP 4, I'm not sure this functionality would be availbale to you).

Fuzzylr

I have php 5 but I'm reading a book trying to learn the different features. Being as I've never really taken an html class I make simple mistakes and so far everyone on here has been real nice to me here so far.

So I'm assuming that php 5 is

$value

??? instead ov Var?

NogDog

In PHP 5 you define it a public, protected, or private. It still supports var and treats it the same as public. See: http://us3.php.net/manual/en/language.oop5.visibility.php

PS: You might find some of the tutorial links (and one book link) useful here: http://www.charles-reace.com/blog/2009/10/27/beginners-corner-learning-object-oriented-php/

nrg_alpha

Nog, I like what you did to your blog (newer theme). Looks great! 🙂
I managed to have a look through that book you suggested (PHP Objects, Patterns and Practice).. looks like it's pretty good indeed.. the only issue I personally have with it is that it seems to lack UML diagrams. When learning OOP, I find UML to be really helpful in visualizing the bigger picture. But in anycase, looks like it would be a solid book for sure.

NogDog

nrg_alpha;10939351 wrote:
Nog, I like what you did to your blog (newer theme). Looks great! 🙂
I managed to have a look through that book you suggested (PHP Objects, Patterns and Practice).. looks like it's pretty good indeed.. the only issue I personally have with it is that it seems to lack UML diagrams. When learning OOP, I find UML to be really helpful in visualizing the bigger picture. But in anycase, looks like it would be a solid book for sure.

The version I have (1st) has a chapter explaining UML class/object diagrams, and uses them throughout the various pattern examples. It also touches on some of the other UML diagram types, but only superficially.