If statements in Controller?

[eluser]industrial[/eluser]
No need to say that i am new @ CI development. You have probably figured that put by my title

Can i use any kind of if/else statements in a controller?

Like following example, based on the shoe-sandal id example shown in user guide (http://ellislab.com/codeigniter/user-gui...passinguri )

Here comes the code:

Code:

<?php
class Products extends Controller {

    if (empty($sandals) && empty($id))
    {    
        echo('in else');
    }
    
    else
    {
        function shoes($sandals, $id)
        {
            echo $sandals;
            echo $id;
        }    
    }
    
}
?>

Thanks a lot!