Python新手困惑：如何优雅地实现面向对象编程？

原创不念不忘少年蓝@ 2025-01-06 17:36 10阅读 0赞

面向对象编程（Object-Oriented Programming，简称OOP）是现代编程的重要方式。以下是一些实现OOP的优雅方法：

1. **继承**（Inheritance）：通过创建子类来继承父类的属性和行为。例如：

```python
class Animal:
    def __init__(self, name):
        self.name = name

class Dog(Animal):
    def bark(self):
        print("Woof!")

dog = Dog('Rex', 'brown')
dog.bark()  # 输出 "Woof!"
```

2. **封装**（Encapsulation）：隐藏对象的实现细节，只对外提供访问接口。例如：

```python
class BankAccount:
    def __init__(self, account_number, balance=0):
        self.account_number = account_number
        self.balance = balance

# 提供对外访问的接口
    def deposit(self, amount):
        self.balance += amount
        print(f"Deposited {amount}. Account balance: {self.balance}.")

def withdraw(self, amount):
        if amount > self.balance:
            print("Insufficient balance!")
            return False

self.balance -= amount
        print(f"Withdrawn {amount}. Account balance: {self.balance}.")

bank_account = BankAccount('123456', 100)
bank_account.deposit(50)  # 输出 "Deposited 50. Account balance: 150."

# 模拟取款
try:
    bank_account.withdraw(200)  # 输入 "Withdrawn 200. Account balance: -50."
except BankAccount.InsufficientBalanceError as e:
    print(e)

```

3. **多态**（Polymorphism）：同一方法在不同子类中有不同的实现。例如：

```python
class Shape:
    def area(self):
        pass  # 返回一个空值，由子类具体实现

class Rectangle(Shape):
    def __init__(self, width, height):
        self.width = width
        self.height = height

def area(self):
        return self.width * self.height

class Triangle(Shape):
    def __init__(self, base, height):
        self.base = base
        self.height = height

def area(self):
        return 0.5 * self.base * self.height

# 使用多态测试
shapes = [Rectangle(3, 4)), Triangle(2, 6)]

for shape in shapes:
    print(f"Area of {shape.__class__.__name__}}: {shape.area()}")
```

通过上述方法，你可以逐步构建一个优雅的面向对象编程系统。