Question

I have a base class Person and derived classes Manager and Employee. Now, what I would like to know is the object created is Manager or the Employee.

The person is given as belows:

from Project.CMFCore.utils import getToolByName
schema = getattr(Person, 'schema', Schema(())).copy() + Schema((TextField('FirstName', required = True, widget = StringWidget(label='First Name', i18n_domain='project')), TextField('Last Name', required = True, widget = StringWidget(label='Last Name', i18n_domain='i5', label_msgid='label_pub_city'))
class Manager(BaseContent):
  def get_name(self):
    catalog = getToolByName(self, "portal_catalog")
      people = catalog(portal_type='Person')
      person={}
      for object in people:
        fname = object.firstName
        lname = object.lastName
        person['name'] = fname+' '+ lname
        # if the derived class is Employee then i would like go to the method title of employee and if its a Manager then go to the title method of Manager
        person['post'] = Employee/Manager.title()
      return person

For Manager and employees they are like (employee is also similar but some different methods)

from Project.Person import Person
class Manager(Person):
    def title(self):
      return "Manager"

For Employee the title is ‘Employee’. When I create a Person it is either Manager or the Employee. When I get the person object the class is Person but I would like to know whether it is from the derived class ‘Manager’ or ‘Employee’.

Answer 1

You can use x.__class__.__name__ to retrieve the class name as a string, e.g.

class Person:
    pass

class Manager(Person):
    pass

class Employee(Person):
    pass

def get_class_name(instance):
    return instance.__class__.__name__

>>> m = Manager()
>>> print get_class_name(m)
Manager
>>> print get_class_name(Employee())
Employee

Or, you could use isinstance to check for different types:

>>> print isinstance(m, Person)
True
>>> print isinstance(m, Manager)
True
>>> print isinstance(m, Employee)
False

So you could do something like this:

def handle_person(person):
    if isinstance(person, Manager):
        person.read_paper()     # method of Manager class only
    elif isinstance(person, Employee):
        person.work_hard()      # method of Employee class only
    elif isinstance(person, Person):
        person.blah()           # method of the base class
    else:
        print "Not a person"