使用while循環

 num = 1
 while num <= 10:
     print(num)
     num += 1

讓用戶選擇何時推出循環

 print("tell me something\n")
 message = ""
 while message != "quit":
     message = input("message:")
     print(message)

 print("tell me something\n")
 message = ""
 while message != "quit":
     message = input("message:")
     if message != "quit":
         print(message)

退出時不會將quit也打印出來

使用標志判斷程序是否處于活動狀態，應為可能需要多個變量決定程序是否需要繼續執行，此例中極active

 print("tell me something\n")
 active = True
 message = ""
 while active:
     message = input("message:")
     if message == "quit":
         active = False
     else:
         active = True
         print(message)

使用break推出循環

 print("tell me something\n")
 active = True
 message = ""
 while active:
     message = input("message:")
     if message == "quit":
         break
     else:
         active = True
         print(message)

continue語句

當程序執行到continue時，程序判斷繼續執行

在while語句中在列表之間移動元素

 un = ["A", "B", "C"]
 ed = []
 while un:
     ing = un.pop()
     print(f"ing>ed:{ing}")
     ed.append(ing)

 for ing in ed:
     print(ing)

刪除列表中的其特定元素

 pets = ["A", "B", "C"]
 print(pets)

 while 'B' in pets:
     pets.remove('B')
 print(pets)

使用用戶輸入填充字典

這是一個調查程序，收集調查者的姓名和回答

 responses = {}  
 active = True         設置標志指出程序是否繼續執行
 while active:
     name = input("please input the name:")     提示輸入調查者的姓名和回答
     response = input("please input the response_you:")
     responses[name] = response
     repeat = input("please choose whether to go Y/N:")    判斷是否還有人要參與調查
     if repeat == "N":
         active = False

 print("\n調查結束")
 for name, response in responses.items():
     print(f"{name} : {response}")