《Python编程从入门到实践》学习笔记——第8-9章【2022.08.08】

#2022.08.08 by zgw

#第八章 函数

#8.1 定义函数

#定义、实参和形参
from dataclasses import field


def greet_user(username):
    print(f"hello, {username}")

greet_user('tom')

#8.2 传递实参

# 位置实参、关键字实参、默认值

#8.3 返回值
print('--------8.3--------')

def get_formatted_name(fname, lname, mname = ''): # 实参可选
    if mname:
        full_name = f"{fname} {mname} {lname}"
    else:
        full_name = f"{fname} {lname}"
    return full_name.title()

musician = get_formatted_name('jimi', 'hendrix')
print(musician)

musician = get_formatted_name('john', 'hooker', 'lee')
print(musician)

#8.4 传递列表

#将列表传递给函数后，函数就可以对其进行修改。
#在函数中对这个列表所做的任何修改都是永久性的。

#8.5 传递任意数量的实参
print("n======传递任意数量的实参==========n")

def make_pizza(*toppings):  # *toppings 创建一个空元组
    print("Make Pizza n")
    for topping in toppings:
        print(topping)
    print('n')

make_pizza('pepproni')
make_pizza('mushroonm', 'green peppers', 'extra cheese')

print("nexame2n")
def build_profile(first, last, **user_info):  #创建空字典
    user_info['first_name'] = first
    user_info['last_name']  = last
    return user_info
user_profile = build_profile('李', '小龙', location = '中国', field = '功夫')
print(user_profile)

#8.6 将函数存储在模块中
print("n-------- 8.6 -------n")
'''
import pizza
import pizza as p

from pizza import make_pizza, f2, ....
from pizza import make_pizza s mp

from pizza import *
'''

#第九章 类
print("n-------------第九章 类 ----------n")

#9.1 创建和使用类

class Dog:
    """一次模拟小狗的类"""

    def __init__(self, name, age):  #self是必须有的，而且是第一个
        '''初始化属性'''

        self.name = name
        self.age = age

    def sit(self):
        print(f"{self.name} 小狗蹲下。")
    
    def rool_over(self):
        print(f"{self.name} 打滚。")

my_dog = Dog('Willie', 6)
print(f"My dog's name is : {my_dog.name}.")
print(f"My dog's age is : {my_dog.age} years old.")

my_dog.sit()
my_dog.rool_over()

#9.2 使用类和实例
print("n---------- 9.2 Car ---------n")

class Car:
    def __init__(self, make, model, year):
        self.make = make
        self.model = model
        self.year = year

    def get_name(self):
        long_name = f"{self.year} {self.make} {self.model}"
        return long_name.title()

my_new_car = Car('audi', 'a6','2022')
print(my_new_car.get_name())

# 给属性指定默认值
# 修改属性的值：1. 直接修改 2.通过方法修改

#9.3 继承
# 父类、子类； 子类继承父类的所有属性和方法
print("n--------- 9.3 继承--------n")
class Car:
    def __init__(self, make, model, year):
        self.make = make
        self.model = model
        self.year = year

    def get_name(self):
        long_name = f"{self.year} {self.make} {self.model}"
        return long_name.title()

class ElectricCar(Car):
    def __init__(self, make, model, year):
        super().__init__(make, model, year)
        self.battery_size = 100
    
    def print_battery(self):
        print(f"此车的电池容量是： {self.battery_size} KWhn")
    
    def fill_gas_tank(self):        #可以重写父类方法
        print("电动车没有油箱。n")

my_tida = ElectricCar('tida', 'auto','2022')
print(my_tida.get_name())
my_tida.print_battery()

#将实例用作属性
'''
class Car:
    --skip--

class Battery:
    --skip--
    def print_battery(self)
        print("-------")

clss ElectricCar(Car):
    def __inin(self, make, model, year)
        super().init(make, model, year)
        self.battery = Battery()

my_car = ElectricCar('bmw', 'electric 400', 2022)
my_car.battery.print_battery()
'''

#9.4 导入类
print("n-------- 9.4 导入类 ---------n")



#9.5 Python标准库
print("n-------- 9.5 Python标准库----- n")

from random import randint, choice
print(randint(1,6))

players = ['aaa', 'bbb','ccc', 'ddd']
print(choice(players))

#9.6 类码风格
print("n9.6 类码风格：n类名采用驼峰命名法，即单词首字母大写。",end = ' ')
print("实例名和模块名采用小写，单词间加下划线。n")