Python 在名称正确之前，如何对其进行循环？

为什么不在你的条件下使用while循环呢。类似于这样，您可以填写以下详细信息：

import re
username = input("Enter your name to start the test: ")
#Prompting the user to input their name

valid = re.match("^[A-Za-z]*$",username)
#A validation of letters only being used

if not valid:
    print("Error! Letters only!")
    username = input("Enter your name: ")

试试这个：

username = input("Enter your name to start the test: ")
while not re.match("^[A-Za-z]*$",username):
    print("Error! Letters only!")
    username = input("Enter your name: ")

---

当您接受空字符串作为有效用户名时，请阅读

的文档？
import re

valid = False

while not valid:
    username = input("Enter your name to start the test: ")
    valid = re.match("^[A-Za-z]*$", username)

    if not valid:
        print("Error! Letters only!")