calling a subclass

[rebecca]

Hello all,

I imagine this is an elementary question but I've searched and couldn't find what I'm looking for.

I've made a class that looks up whois information, and there's a class that handles top level domain extensions generally, from that class I'm making a series of subclasses that will be called depending on what sort of extension it is.

If it's a certain whois server then it calls handler 1, if another then handler 2 is called, and so forth.

What I need to know is how to call different subclasses of the extension handler depending on a variable ($handler) (which I will extract from the database) from within the whois class constructor.

I hope that makes sense :-) I will appreciate any and all help, as per usual you guys are great.
cheers, Rebecca

[toma42]

$class = new $handler;
where handler is the name of the subclass and the extention.

There's a better way, however. Look at how pear does database abstraction and, modeling it, create a handler function on the base class to take care of which object to instantiate such as

$class = WHOIS:connect($extension);

so the connect function takes care of what subclass to return.

[rebecca]

could (from your example) $class and $handler actually be variables within the context of the code then?

for example, the database sends back the handler to be used, puts it into a variable called handler and then I could actually write:

$handler = new $handler;

If not, could you please tell me where can I find the information about pear?

thank-you,
rebecca

[toma42]

pear.php.net

Not a lot of docs but you'll find some great links to get you started in the user comments here: http://php.net/pear