当出现错误时，如何使程序继续/重新启动？

Question

当我学习python时，我创建了这个代码，但问题是当有人键入与stm或mts不同的内容时，它只是打印错误消息并停止，我需要它继续并重新运行代码，所以我添加了一个While循环，其中包含一个continue语句，但它不能正常工作，它只是不断发送错误消息，请任何想法如何使我的代码继续运行，而不是垃圾邮件或停止后，它..谢谢你这么多

代码如下：

print("Welcome to MoroccanDirham_SaudiRiyal converter program!")

def mConv():
    def rial_saudi_to_moroccan_dirham(sar):
        amount = sar * 2.67
        print("Here is the result: ", amount, "MAD")

    def moroccan_dirham_to_rial_saudi(mad):
        amount = mad * 0.37
        print("Here is the result: ", amount, "SAR")
    usChoice = str(input("For SAR to MAD type stm and for MAD to SAR type mts: "))

    while True:
        if usChoice == str("stm"):
            x = int(input("Type the amount of money you want to convert: "))
            rial_saudi_to_moroccan_dirham(x)
            return False
        elif usChoice == str("mts"):
            y = int(input("Type the amount of money you want to convert: "))
            moroccan_dirham_to_rial_saudi(y)
            return False
        elif usChoice != str("stm") or usChoice != str("mts") :
            print("Error! Please choose between stm and mts.")
            continue
            return False
        else:
            return True
mConv()

Answer 1

Move usChoice=str（输入（“对于SAR to MAD type stm和对于MAD to SAR type mts:”）） 在while循环中，删除最后一条else语句，不应该在那里输入return，您可以编写一条错误消息

print（“欢迎来到Morocandirham\u SaudiRiyal converter program！”）

def mConv():
    def rial_saudi_to_moroccan_dirham(sar):
        amount = sar * 2.67
        print("Here is the result: ", amount, "MAD")

    def moroccan_dirham_to_rial_saudi(mad):
        amount = mad * 0.37
        print("Here is the result: ", amount, "SAR")


    while True:
        usChoice = str(input("For SAR to MAD type stm and for MAD to SAR type mts: "))
        if usChoice == str("stm"):
            x = int(input("Type the amount of money you want to convert: "))
            rial_saudi_to_moroccan_dirham(x)
            return False
        elif usChoice == str("mts"):
            y = int(input("Type the amount of money you want to convert: "))
            moroccan_dirham_to_rial_saudi(y)
            return False
        else:
            print("Invalid choice. Allowed choices");
            print("stm - rial to dirham");
            print("mts - dirham to rial");
mConv()