Objects With Object Properties

mindschreck

Greets,

I have a quick question. I have a class called CPatient. This class has a property called $m_Skeleton. $m_Skeleton is a CSkeleton object, and is created on the construction of CPatient.

Is there a way from within CSkeleton that I can refer directly to the parent properties. I can always pass the values down from the patient to the skeleton, but I would like to access them directly.

For example:

class CPatient{
var $m_Age;
var $m_Skeleton;

function CPatient() {
$this->m_Skeleton = new CSkeleton();
}
}

class CSkeleton{
var $m_BoneDensity;

function CSkeleton() {
// Bone density is calc based on
// patient's age
$this->m_BoneDensity = Parent->m_Age * whatever.
}
}

I essentially want to calculate someting in the Skeleton that needs access to the Patient's age. I can pass the age into the constructor of Skeleton, but I don't want to do that, especially if Skeleton grows and I end up having to pass scores of variables redundantly.

Any help is appreciated!

Cheers,
Jason

Anon

This may not be at all what you want to do but by extending the parent class you then have access to its values.

class CPatient{
var $m_Age;
var $m_Skeleton;

function CPatient() { 
	$this->m_Age = '22222';
}

}

class CSkeleton extends CPatient{
var $m_BoneDensity;

function CSkeleton() { 
	$this->CPatient();

	$this->m_BoneDensity = $this->m_Age; 
}

}

// code to instantiate
$xyz = new CSkeleton();
echo ($xyz->m_BoneDensity);

mindschreck

Hi all,

I found a solution to my problem:

class CPatient{
var $m_Age;
var $m_Skeleton;

function CPatient() {
$this->m_Skeleton = new CSkeleton($this);
}
}

class CSkeleton{
var $m_BoneDensity;
var $m_Parent;

function CSkeleton(&$Parent) {
// Set pointer to parent
$this->m_Parent = &$Parent;
}

function GetDensity() {
// Bone density is calc based on
// patient's age
$this->m_BoneDensity = $this->m_Parent->m_Age * whatever.
}
}

At first, this code did not work when I created my patient:

$Patient = new CPatient();
$Patient->m_Age = 22;
// This fetched a NULL age, thus making
// the calc wrong
$Patient->m_Skeleton->GetDensity();

However, changing the instantiation of the parent worked like a charm:

// Note reference to $Parent
$Patient =& new CPatient();
$Patient->m_Age = 22;
// Calc works. Age fetched
$Patient->m_Skeleton->GetDensity();

Hope this helps anyone with this problem. BTW, I found the solution at Zend, under their OOP for PHP section.

Cheers,
Jason