[PHP] Re: "Bless"ing an object

[Greg Beaver]

Wouter,

you could try this adding this method to each object you need blessings 
from:

function &bless($classname)
{
    if ($classname == get_class($this)) {
        return $this;
    }
    $vars = get_object_vars($this);
    $ret = new $classname;
    return $ret->loadValues($vars);
}
function &loadValues($vals)
{
    foreach ($vals as $name => $val) {
        $this->$name = $val;
    }
    return $this;
}
In the Load() method, you should determine what class you need, and call 
$ret = &$this->bless('classname'), and then return $ret.

Then, instead of doing

$Thing->Load();

do

$Thing = &$Thing->Load();

and have Load() return an object instance (either $this or the newly 
blessed object).

This will maintain encapsulation and achieve the results you're looking for.

Regards,
Greg
Wouter Van Vliet wrote:
Hi Folks

I was wondering (mostly because I came across some situations where I need
it) if PHP supplies any methods to "bless" an array or object to become some
other object. In perl, I can simply do:
        my $SomeInstance = bless { item => 'value', 'Item2' => 'value2' },
'SomeObject';
And then if I decide that $SomeInstance should be an intance of some other
object:
	bless $SomeInstance, 'OtherObject';

In PHP it would be extremely useful for for doing something like this:

<?php
Class Foo {
        
        Load() {
                ( .. )
        }
};

Class Bar extends Foo {

}

$Thing = new Foo();
$Thing->Load();
?>
In Load the object data is loaded from the database, and now imagine one row
to contain the subclass this instance of Foo should become. I then would
want $Thing to become and thus behave like an instance of Bar (if my
database row says so).
Hope this message wasn't too confusing ;)
Wouter
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