[Editor's note: If you are trying to do overriding, then you can just
interrogate (perhaps in the method itself) about what class (get_class())
the object belongs to, or if it is a subclass of a particular root class.

You can alway refer to the parent overriden method, see the "Classes
and Objects" page of the manual and comments/editor's notes
therein.]

There is no function to determine if a member belongs to a base class or
current class eg:

class foo {
 function foo () { }
 function a () { }
}

class bar extends foo {
 function bar () { }
 function a () { }
}

lala = new Bar();
------------------
how do we find programmatically if member a now belongs to class Bar or
Foo.

i came across an errer something to the extent:

Fatal error: The script tried to execute a method or access a property of
an incomplete object. 

This was because I had included the file defining the class when i created
the object but not in the script when i was trying to access the object as
a member variable of a different object

I spent 20 minutes or so trying to figure this out, maybe someone else has
the same problem.

To access a class' function from within the class you would have to say
$this->functionname(params), rather than just functionname(params) like
in other programming languages.

Hope this helps

New to OOP?  This listing of beginner PHP OOP tutorials may help:
  

array in class ^^

class CConfig
{
    var $color = array(
        'top'     => "",
        'write'   => "",
        'reply'   => "",
        'bottom1' => "",
        'bottom2' => "",
        'bottom3' => ""
    );
}

don't do var color['write'];

Something nice i found out when i was trying to do with classes what i knew
could be done with
functions: they can be dynamically loaded/used.

ex:

class a
{
        function bla()
        {
                echo "1\n";
        }
}

class b
{
        function bla()
        {
                echo "2\n";
        }
}

$class = "a";

$test = new $class;
$test->bla();

$class2 = "a";

$test2 = new $class2;
$test2->bla();

-----------------------

This will print:

1
2

------------------

For those of you who were considering doing something with plugins....use
this to your
advantage :)

makes life soooo easy, this :)

Sar

Actually, that example prints "1" and then "1", rather
than "1" and then "2". I'm assuming the typo is that
it should read $class2 = "b" instead of a.

another way to dynamically load your classes: 

==========================
function loadlib($libname) {
     $filename = "inc/".$libname.".inc.php";
     // check if file exists...
     if (file_exists($filename)) {
          // load library	
          require($filename);
          return TRUE;
     }
      else {
	// print error!
	die ("Could not load library $libname.\n");
     }
}

:) 

have phun!

-cornelius

This is a pretty basic data structure, I know, but I come from a C++
background where these things were "da bomb" when I was first
learning to implement them. Below is a class implementation for a queue
(first-in-first-out) data structure that I used in a recent project at my
workplace. I believe it should work for any type of data that's passed to
it, as I used mySQL result objects and was able to pass the object from
one page to another as a form element.

# queue.php

# Define the queue class
class queue
{
	# Initialize class variables
	var $queueData = array();
	var $currentItem = 0;
	var $lastItem = 0;
	
	# This function adds an item to the end of the queue
	function enqueue($object)
	{
		# Increment the last item counter
		$this->lastItem = count($this->queueData);
		
		# Add the item to the end of the queue
		$this->queueData[$this->lastItem] = $object;
	}
	
	# This function removes an item from the front of the queue
	function dequeue()
	{
		# If the queue is not empty...
		if(! $this->is_empty())
		{
			# Get the object at the front of the queue
			$object = $this->queueData[$this->currentItem];
			
			# Remove the object at the front of the queue
			unset($this->queueData[$this->currentItem]);
			
			# Increment the current item counter
			$this->currentItem++;
			
			# Return the object
			return $object;
		}
		# If the queue is empty...
		else
		{
			# Return a null value
			return null;
		}
	}
	
	# This function specifies whether or not the queue is empty
	function is_empty()
	{
		# If the queue is empty...
		if($this->currentItem > $this->lastItem)
			
			# Return a value of true
			return true;
			
		# If the queue is not empty...
		else
		
			# Return a value of false
			return false;
	}
}

?>

# Examples of the use of the class

# Make sure to include the file defining the class
include("queue.php");

# Create a new instance of the queue object
$q = new queue;

# Get data from a mySQL table
$query = "SELECT * FROM " . TABLE_NAME;
$result = mysql_query($query);

# For each row in the resulting recordset...
while($row = mysql_fetch_object($result))
{
	# Enqueue the row
	$q->enqueue($row);
}

# Convert the queue object to a byte stream for data transport
$queueData = ereg_replace("\"", """,
serialize($q));

# Convert the queue from a byte stream back to an object
$q = unserialize(stripslashes($queueData));

# For each item in the queue...
while(! $q->is_empty())
{
	# Dequeue an item from the queue
	$row = $q->dequeue();
}