Python：函數定義在所需輸出的中間不斷返回'None'

Question

好吧，所以我正在爲我們的女朋友製作我們的6週年代碼。 我是一個完整的編程noob。我正在編寫一些非常簡單的代碼，基本上是一個輸入數字輸入機器，以便用戶（她）接收字符串輸出。

我一直看到「無」，當我運行我的代碼。爲什麼？ 在這裏。

def love(n): 
    if n < 0 : 
    print "Why would it be negative?!" 
    if n == 0 : 
     print "well that is just hurtful" 
    if n == 1 : 
    print "I REALLY love you" 
    if n == 2 : 
    print "You make me smile at least once, each and every day" 
    if n == 3 : 
    print"you wouldn't believe how annoying it was to get this program to run properly! but it was worth it" 
    if n == 4 : 
     print "let's " + "shoot a little higher than that" 
    else: 
    print "I honestly can't see myself without you anymore" 


print love(0) 

print "Wanna try again? :D " 

Answer 1

你的函數具有None默認的返回值，所以當你print出來，將打印None。

只需調用沒有print語句的函數即可。

或者，您可以將函數中的所有print語句替換爲return，並將其變爲if-elif-else塊，因爲它們都是互斥的操作。然後，打印love(0)實際上會打印出返回值。

Answer 2

love(0) # is all you need. 

---

你不需要調用print love()，因爲你已經擁有內love打印報表。 你正在看到None爲love正在做所有的工作，它沒有返回任何東西。

---

另外，你需要爲你只想要一個，出所有的打印操作的，在同一時間運行，以使用if-elif-else塊的功能。

if n < 0 : 
    print "Why would it be negative?!" 
elif n == 0 : 
     print "well that is just hurtful" 
elif n == 1 : 
    print "I REALLY love you" 
elif n == 2 : 
    print "You make me smile at least once, each and every day" 
elif n == 3 : 
    print"you wouldn't believe how annoying it was to get this program to run properly! but it was worth it" 
elif n == 4 : 
     print "let's " + "shoot a little higher than that" 
else: 
    print "I honestly can't see myself without you anymore" 

雖然，超越2，打印一切不會傷害;）

_{我100 ^日答案就這樣！好極了 ！}