Python while/try/if循環

Question

我剛剛學習python，想知道是否有更好的方法來編寫代碼，而不是在while循環中使用try/except和if/else。這是從學習編碼困難的方式，我試圖給用戶3次機會輸入一個數字，在第三次使用死亡函數退出的機會。 （該評論是爲了我自己）

def gold_room(): 
    print "this room is full of gold. How much do you take?" 
    chance = 0 #how many chances they have to type a number 
    while True: #keep running 
     next = raw_input("> ") 
     try: 
      how_much = int(next) #try to convert input to number 
      break #if works break out of loop and skip to ** 
     except: #if doesn't work then 
      if chance < 2: #if first, or second time let them try again 
       chance += 1 
       print "Better type a number..." 
      else: #otherwise quit 
       dead("Man, learn to type a number.")  
    if how_much < 50: #** 
     print "Nice, you're not greedy, you win!" 
     exit(0) 
    else: 
     dead("You greedy bastard!") 

def dead(why): 
    print why, "Good bye!" 
    exit(0) 

Answer 1

下面是一個使用遞歸的另一種方法：

def dead(why): 
    print why, "Good bye!" 
    exit(0) 

def typenumber(attempts): 
    if attempts: 
     answer = raw_input('> ') 
     try: 
      int(answer) 
     except ValueError: 
      print "Better type a number..." 
      return typenumber(attempts -1) 
     else: 
      return True 

if typenumber(3): 
    print 'you got it right' 
else: 
    dead("Man, learn to type a number.") 


> a 
Better type a number... 
> b 
Better type a number... 
> 3 
you got it right 

這是您提供什麼樣的精簡版，缺少了大部分的味道文字，但希望它可以爲您提供更多關於其他方法的信息，以便對您的值進行封裝而不是硬編碼。

Answer 2

相反的包裹你的try在while循環，我可能會移動的except內while循環，使你的代碼更有條理，更易於閱讀，Python的前提。下面是一個可以複製並運行的示例：

def gold_room(): 
    print "this room is full of gold. How much do you take?" 
    while True: #keep running 
     next = raw_input("> ") 
     try: 
      how_much = int(next) #try to convert input to number 
      break #if works break out of loop and skip to ** 
     except: #if doesn't work then 
      while True: 
       chance = 0 #how many chances they have to type a number 
       if chance < 2: #if first, or second time let them try again 
        chance += 1 
        print "Better type a number..." 
       else: #otherwise quit 
        dead("Man, learn to type a number.")  
    if how_much < 50: #** 
     print "Nice, you're not greedy, you win!" 
     exit(0) 
    else: 
     dead("You greedy bastard!") 

def dead(why): 
    print why, "Good bye!" 
    exit(0) 

gold_room()