python - 字符串检查器，无效输入 - Python

Question

它不会打印不要将用户名留空，因为当我按 Enter 时输入无效（空白输入）

def strchecker(question):
    valid=False
    while not valid:
        user_Name = input(question)
        if user_Name!="":
            valid=True
            return user_name
        else:
            print("Do no leave username blank")

print("*************Welcome to the Te Reo Maori Quiz***************")
user_Name = str(input("Please enter your username")) 

标签： python

Answer 1

您实际上并没有调用该函数；这可能就是它不起作用的原因。尝试这个：

def strchecker(question):
    while True:
        user_Name = input(question)
        if user_Name:
            return user_Name  # Make sure to capitalize the N in user_Name
            break
        else:
            print("Do no leave username blank")

print("*************Welcome to the Te Reo Maori Quiz***************")
user_Name = strchecker("Please enter your username") 

这应该有效。