Guibs 的 Python学习_ 函数

# 函数# 函数是带有名字的代码块, 用于完成具体的工作# 定义函数 greet_userdef greet_user():    # 函数体    print("Hello")# 调用函数 greet_usergreet_user()# 向函数传递信息def greet_user(username): # username 是一个形参    print("Hello " + username)greet_user(username='Guibs') # Guibs 是一个实参greet_user('Guibs')# 带关键字传递实参# 可以不用考虑实参传递的顺序def greet_user(username1, username2):    print("Hello " + username1 + " and " + username2)greet_user(username2='Guibs', username1='Guibs82')# 参数默认值# 若不传递参数则调用默认值# 含有默认值的参数必须放在后面def greet_user_with_default_name(username1, username2='Guibs82'):    print("Hello " + username1 + " and " + username2)# 若未传递足够参数, 则按位置进行参数传递greet_user_with_default_name('G')# 返回值def get_formatted_name(first_name, last_name, middle_name = ""):    if middle_name:        full_name = first_name + " " + middle_name + " " + last_name    else:        full_name = first_name + " " + last_name    return full_name.title()my_name = get_formatted_name("guibs", "g")print("My name is " + my_name)my_name = get_formatted_name("guibs", 'g', '82')print("My name is " + my_name)# 返回字典def build_person(first_name, last_name, age=''):    '''返回一个字典, 包含有关一个人的信息'''    person = {        'first': first_name.title(),        'last': last_name.title(),    }    if age:        person['age'] = age    return personprint(build_person('g', 'ghost', 22))# 传递列表names = ['guibs', 'ghostg', 'rio_G']def greet_users(names):    for name in names:        print("Hello " + name.title())greet_users(names=names)# 在函数中修改列表# 将列表传递给函数后, 函数可以对其进行永久性修改unprinted_designs = ['iphone case', 'ipad case', 'mac case']printed_designs = []def print_designs(unprinted_designs, printed_designs):    while unprinted_designs:        current_design = unprinted_designs.pop()        print("准备打印: " + current_design)        printed_designs.append(current_design)        print("打印完毕: " + current_design)    print("全部作品打印完毕")print_designs(unprinted_designs=unprinted_designs, printed_designs=printed_designs)def show_printed_designs(printed_designs):    print("打印完毕的作品: ")    for printed_design in printed_designs:        print(printed_design)show_printed_designs(printed_designs)# 禁止函数修改列表# 采用切片的形式, 复制传入函数的列表unprinted_designs = ['iphone case', 'ipad case', 'mac case', 'apple watch case']printed_designs = []print_designs(unprinted_designs[:], printed_designs)print(unprinted_designs) # 此时, 原列表未被修改# 传递任意数量的参数# [*param_name]# 此时, Python 将参数封装至一个元组def print_username(*username):    print(username)print_username("Guibs")print_username("Guibs", 'GhostG')# 使用任意数量的关键字形参# [**param_names]def set_hobbies(name, **hobbies):    my_hobbies = {}    my_hobbies['name'] = name    for key, value in hobbies.items():        my_hobbies[key] = value    return my_hobbiesprint(set_hobbies(name="Guibs", hobby_1='Swift', hobby_2='Python'))# 注意: 在 import 时, 若不使用系统中的解释器, 而是用自己创建的, 则报错# 导入存储在模块中的函数# 导入整个模块import pizzapizza.make_pizza(12, 'mushrooms', 'extra cheese')# 使用 as 给模块指定别名import pizza as pp.make_pizza(12, 'mushrooms', 'lots of cheese')# 导入特定的函数# from module_name import function_name_0, function_name_1, ...# 这种语法可以无需使用 .from pizza import make_pizzamake_pizza(12, 'mushrooms', 'more cheese')# 使用 as 给函数指定别名from pizza import make_pizza as buy_pizzabuy_pizza(12, 'mushrooms', 'a lot of cheese')# 导入模块中的所有函数# [*]from pizza import *get_price()

运行上方代码另需新建 pizza.py

def make_pizza(size, *toppings):    '''概述要制作的披萨'''    print("做一个尺寸为: " + str(size) + ", 包含: ")    for topping in toppings:        print("- " + topping)    print("的披萨")def get_price():    print("The price is 20")