First-Class Object :函數
在 Python 中萬物皆爲對象,函數也不例外,函數做爲對象能夠賦值給一個變量、能夠做爲元素添加到集合對象中、可做爲參數值傳遞給其它函數,還能夠當作函數的返回值,這些特性就是第一類對象所特有的。code
name = 'tank' dsb = name def index(): print('from index') a = index a()
def foo(x, y, func): print(x, y) func() def bar(): print('from bar') foo(1, 2, bar)
傳參的時候沒有特殊需求,必定不要加括號,加括號當場執行了對象
def index(): print("from index") def func(a): return a a = func(index) # print(a) a()
def func(): print('from func') l1 = [1, '2', func, func()] f = l1[2] print(f)
def registers(): print('register') def login(): print('login') def shopping(): print('shopping') def pay(): print('pay') choice_dic = { '1': registers, '2': login, '3': shopping, '4': pay, } def choice(): while True: print(''' 1 : 註冊 2 :登陸 3 :購物 4 :付款 5 :退出''') num = input('請輸入數字進行選擇:').strip() if num == '5': break if num not in choice_dic: continue else: choice_dic[num]() choice()