Python面向对象进阶

心已赠人 2022-04-25 08:16 181阅读 0赞

# 1.@property装饰器 #

类似java里的get, set方法。  
复杂版：

class Student(object):
    
        def get_score(self):
             return self._score
    
        def set_score(self, value):
            if not isinstance(value, int):
                raise ValueError('score must be an integer!')
            if value < 0 or value > 100:
                raise ValueError('score must between 0 ~ 100!')
            self._score = value

使用@property装饰器版：

class Student(object):
    
        @property
        def score(self):
            return self._score
    
        @score.setter
        def score(self, value):
            if not isinstance(value, int):
                raise ValueError('score must be an integer!')
            if value < 0 or value > 100:
                raise ValueError('score must between 0 ~ 100!')
            self._score = value

# 2.继承 #

class Person(object):
        def __init__(self, name, age):
            self._name = name
            self._age = age
    
        @property
        def name(self):
            return self._name
    
        @property
        def age(self):
            return self._age
    
        @age.setter
        def age(self, age):
            self._age = age
    
        def play(self):
            print('%s正在愉快的玩耍' % self._name)
    
        def watch_movies(self):
            if self._age >= 18:
                print('%s正在观看《一拳超人》.' % self._name)
            else:
                print('%s只能观看《喜洋洋》.' % self._name)
    
    class Student(Person):
        def __init__(self, name, age, grade):
            super().__init__(name, age)
            self._grade = grade
    
        @property
        def grade(self):
            return self._grade
    
        @grade.setter
        def grade(self, grade):
            self._grade = grade
    
        def study(self, course):
            print('%s的%s正在学习%s.' % (self._grade, self._name, course))
    
    def main():
        stu = Student('郭德纲', 42, '初三')
        stu.study('数学')
        stu.watch_movies()
    if __name__ == '__main__':
        main()

# 3.重载 #

from abc import ABCMeta, abstractclassmethod
    
    class Employee(object, metaclass=ABCMeta):
        def __init__(self, name):
            self._name = name
    
        @property
        def name(self):
            return self._name
    
        @abstractclassmethod
        def get_salary(self):
            pass
    
    class Manager(Employee):
        # 想一想: 如果不定义构造方法会怎么样
        def __init__(self, name):
            # 想一想: 如果不调用父类构造器会怎么样
            super().__init__(name)
    
        def get_salary(self):
            return 15000.0
    
    class Programmer(Employee):
        def __init__(self, name, working_hour):
            super().__init__(name)
            self._working_hour = working_hour
    
        @property
        def working_hour(self):
            return self._working_hour
    
        @working_hour.setter
        def working_hour(self, working_hour):
            self._working_hour = working_hour if working_hour > 0 else 0
    
        def get_salary(self):
            return 150.0 * self._working_hour
    
    class Salesman(Employee):
        def __init__(self, name, sales):
            super().__init__(name)
            self._sales = sales
    
        @property
        def sales(self):
            return self._sales
    
        @sales.setter
        def sales(self):
            self._sales = sales if sales > 0 else 0
    
        def get_salary(self):
            return 1200.0 + self._sales * 0.05
    
    def main():
        emps = [
            Manager('刘备'), Programmer('诸葛亮', 150), Salesman('荀彧', 10000)
        ]
        for emp in emps:
            print('%s本月工资为: ￥%s元' % (emp.name, emp.get_salary()))
    
    
    if __name__ == '__main__':
        main()