OOP Basics

Procedural Programming: Regular programming with functions and stuff

• Methods: Something an object does
• Attributes: Something an object has

car = CarBlueprint()
# car -> object, CarBlueprint() -> class

Create Class & Object

class WebUser:
	pass
user1 = WebUser()

Create Object & Add Attribute

user1 = WebUser()
user1.id = '001'
user1.username = 'atakan'
 
print(user1.username) # will print atakan

Initialize / Construct

When creating an object from a class, you can create attributes manually like above. However, it is hard and error-prone. To simplify, you use constructs or initialize an object.

In python, you do this using __init__.

class Car:
	def __init__(self):
	# initialize attributes

Every time an object is created, init function will be called.

• “self” keyword is used to assign attributes to the object being created.

class User:
    def __init__(self,name='default_name'):
        self.username = name
        self.followers = 0 ## You can give attributes without any passing
user_1 = User('atakan')
user_2 = User('ela')

To have a placeholder in a parameter, you can use __init__(self, name='placeholder').

Add Methods

class Car:
	def enter_race_mode(self):
		self.seats = 2

You generally need to give the “self” as the first parameter to change anything about the object

The ‘init’ method runs first when you create an object. Then, you can change a value assigned by ‘init’ by using any method