Python应该返回str返回'None'

Question

我正在制作一个刽子手计划(这是一个家庭作业),这是告诉玩家到目前为止他们已经猜到了什么的部分.这是我的编程:

def getGuessedWord(secretWord, lettersGuessed):
theWord=''
for char in secretWord:
    if char not in lettersGuessed:
        char='_ '
        theWord+=char
    elif char in lettersGuessed:
        theWord+=char
    else:
        return theWord
print (getGuessedWord('apple', ['e', 't', 'i', 'p', 'r']

当我要求它打印出来theWord时,我希望它能发出一份下划线和字母的组合_ pp_ e,而是给了我None.我无法弄清楚我的问题是否是我theWord在第2行放置的地方,或者是否与其他地方有关,或者它是否完全不同.

Answer 1

return在成功执行整个for循环之后你需要做些什么:

def getGuessedWord(secretWord, lettersGuessed):
   theWord=''
   for char in secretWord:
      if char not in lettersGuessed:
         char='_ '
         theWord+=char
      elif char in lettersGuessed:
         theWord+=char
   return theWord #here, returning theWord
print (getGuessedWord('apple', ['e', 't', 'i', 'p', 'r']))