Question

我正在创建一个基本登录名，以验证输入的密码和该密码的确认是否匹配。

def login():  
  username = input("Please enter a username:")
  password = input("Please enter a password:")
  confirmPass = input("Please confirm your password:")

login()

if password == confirmPass:
  print("You have signed up")

我收到未定义名称密码的错误。

Answer 1

函数login中的变量限于函数login的作用域。

您可以将支票移到该功能内：

def login():  
  username = input("Please enter a username:")
  password = input("Please enter a password:")
  confirmPass = input("Please confirm your password:")
  if password == confirmPass:
    print("You have signed up")

login()

其他可能性：

使用全局变量
使函数login返回一个布尔值并检查返回值

Answer 2

您接近了，只需从函数中返回password, confirm_pass中的值即可。同样，snake_case不是camelCase https://www.python.org/dev/peps/pep-0008/

def login():  
    username = input("Please enter a username:")
    password = input("Please enter a password:")
    confirm_pass = input("Please confirm your password:")
    return password, confirm_pass

password, confirm_pass = login()

if password == confirm_pass:
    print("You have signed up")

Answer 3

我认为这就是你想要的，我添加了一个额外的和平（如果你想要复制）：

name = input("enter a username: ")
password = input("enter a password")
repass = input("retype your passsword: ")

if password == repass:
 print("signed in.")
else:
 print("passwords do not match..")

#extra copy if you want...
name1 = input("enter a username: ")
password1 = input("enter a password: ")

if password1 == repass:
 if name1 == name:
  print ("logged in.")
 else:
   print("incorrect username")
else:
 print("incorrect password.")

Answer 4

我宁愿从函数中返回值-但是如果您想使用模块级全局变量，只需在调用username之前定义password和login()。

类似的东西：

def login():  
    username = input("Please enter a username:")
    password = input("Please enter a password:")
    confirmPass = input("Please confirm your password:")

username = ""
password = ""

login()

if password == confirmPass:
    print("You have signed up")

我相信，这应该可以按您预期的方式工作。

Answer 5

如果不确定，最好不要在函数内声明任何变量。尝试以下代码：

username = input("Please enter a username:")
password = input("Please enter a password:")
confirmPass = input("Please confirm your password:")

def match_password(password,confirmPass):  
    if password == confirmPass:
        print("You have signed up")
    else:
        print("Passwords do not match")

match_password(password,confirmPass)

所有变量都是根据函数外部的输入声明的，以验证密码。

NameError：在if语句中使用名称时未定义名称

5 个答案: