Method

Classes can be broken into two core parts:

• The data that is attributed to a class’s members or properties.
• The behaviors that are defined or inherited in the class.

Methods are the “behavior” part of the class. When an instance variable is created from a class, it has access to the class’s associated methods. Methods can accept parameters (sometimes they’re called “arguments”) and can return a result.

In object-oriented programming, methods promote reusability and keep functionality encapsulated inside an object.

Example

In the Python example below, a class for a character in a game, Character, is defined with certain behaviors. The character can:

• Introduce themselves via .introduceSelf().
• Move left given an integer amount via .moveLeft().
• Move right given an integer amount via .moveRight().

class Character:
  def __init__(self, name, movex):
    self.name = "Player"  # Character's name
    self.movex = 0        # Character's starting position

  def introduceSelf(self):
    # Print out an introduction phrase
    print(f"Hello! I'm {self.name}.")

  def moveLeft(self, x):
    # Move the character left by x pixels
    self.movex -= x

  def moveRight(self, x):
    # Move the character right by x pixels
    self.movex += x

Now, when an instance of Character is created, the game character can introduce themselves, move left, or move right.

Methods in Different Languages

• Methods in C++
• Methods in Java
• Methods in JavaScript
• Methods in Python