Question

如果用户输入'no'进行打印（M1），如何停止运行最后一个打印语句？我希望程序在打印M1时完成。我收到了错误 “NameError：名称'TaxCode'未定义”当用户输入'no'时，因为在if块中声明'TaxCode'。谢谢。

~/Library/MobileDevice/Provisioning Profiles

Answer 1

在if语句之前使用空值定义TaxCode以防止NameError。这样TaxCode =''

你可以使用exit(0)来终止程序里面的数字（）里面指的是成功/失败。与linux中的退出状态相同。所以你的代码将是

while Q1 != "yes" and Q1 != "no":
    print("\nPlease enter either 'yes' or 'no'")
    Q1=input("Do you recieve an income tested benefit? ")
    if Q1=="yes":
        Q2=input("Is this tax code for the income tested benefit? ")
         while Q2 != "yes" and Q2 != "no":
             print("\nPlease enter either 'yes' or 'no'")
             Q2=input("Is this tax code for the income tested benefit? ")
             TaxCode='' #define it before using
             if Q2=="yes":
                 TaxCode = "M"
             elif Q2=="no":
                  print (M1)
                  exit(0) # terminates program and raises success non-zero value refers failure.

print("Thanks for answering the questions.",name,"Your tax code is ",TaxCode)

如果您在函数中使用上述代码并且想要停止该函数，则可以使用return语句通过返回None来跳过打印最后一行，因此在这种情况下您的代码将是。< / p>

while Q1 != "yes" and Q1 != "no":
    print("\nPlease enter either 'yes' or 'no'")
    Q1=input("Do you recieve an income tested benefit? ")
    if Q1=="yes":
        Q2=input("Is this tax code for the income tested benefit? ")
         while Q2 != "yes" and Q2 != "no":
             print("\nPlease enter either 'yes' or 'no'")
             Q2=input("Is this tax code for the income tested benefit? ")
             TaxCode='' #define it before using
             if Q2=="yes":
                 TaxCode = "M"
             elif Q2=="no":
                  print (M1)
                  return None # skips print and returns to calling function.
print("Thanks for answering the questions.",name,"Your tax code is ",TaxCode)

您可以根据您的逻辑使用exit或return，因为您不清楚此代码是用于函数还是主要用于解释这两个。

Answer 2

您应该定义＆＃39; TaxCode＆＃39;在if语句之外。

例如，

TaxCode = ""
Q1=input("Do you receive an income tested benefit? ")
while Q1 != "yes" and Q1 != "no":
    print("\nPlease enter either 'yes' or 'no'")
    Q1=input("Do you recieve an income tested benefit? ")
if Q1=="yes":
                 Q2=input("Is this tax code for the income tested benefit? ")
                 while Q2 != "yes" and Q2 != "no":
                     print("\nPlease enter either 'yes' or 'no'")
                     Q2=input("Is this tax code for the income tested benefit? ")
                 if Q2=="yes":
                                TaxCode = "M"
                 elif Q2=="no":
                                  print (M1)

print("Thanks for answering the questions.",name,"Your tax code is ",TaxCode)

Answer 3

就像@Navieclipse提到的那样，你需要在使用之前定义TaxCode。

name = input("What is your name? ")
while True:
    try:
        income = int(input("What is your income? ($) "))
        break
    except ValueError:
        print ("Invalid input\nPlease enter a figure")
        continue
    else:
        break

TaxCode = ""
M1  = "This program cannot determine your tax code. Please use the program for secondary income "

print("Please answer the questions with 'yes' and 'no'")

while True:
    Q1=input("Do you receive an income tested benefit? ")
    if Q1 == "yes":
        Q2=input("Is this tax code for the income tested benefit? ")
        if Q2 == "yes":
            TaxCode = "Test"
            print("Thanks for answering the questions, "+ name + ", " + "your tax code is " + TaxCode + ".")
            break
        elif Q2 == 'no':
            print(M1)
            break
    else:
        print("\nPlease enter either 'yes' or 'no'")

此外，将其复制到此处后对其进行格式化会使其更易于阅读。

阻止命令运行

3 个答案: