重新启动循环以迭代用户字符串[重复]答案

【问题标题】：Restarting loop to iterate over a user string [duplicate]重新启动循环以迭代用户字符串[重复]
【发布时间】：2019-08-01 06:05:57
【问题描述】：

我正在尝试接受用户输入并检查字符串中的非字母值。我的问题是如果他们输入了错误的值，我该如何再次查询它们并重新开始循环？见下文

name = str(input("Enter name:"))

for i in name:
     if not i.isalpha():
          name = str(input("Enter name:")
          **line to start iterating from the beginning with new entry.**

只是试图验证用户只输入字母。如果检查失败，他们会再次输入名称并重新开始。提前致谢！

【问题讨论】：

您使用循环直到您的验证匹配...查看副本。

标签： python python-3.x loops for-loop

【解决方案1】：

你可以这样做：

correct = False
while correct == False:

    name = str(input("Enter name:"))
    for i in name:
        if not i.isalpha():
            correct = False
            break
        else:
            correct = True

【讨论】：

【解决方案2】：

您可以在下面看到一个示例代码：

while True:
    number_found = False
    name = str(input("Enter name:"))
    for i in name:
        print("Check {} character".format(i))
        if i.isdigit():
            print("{} is number. Try again.".format(i))
            number_found = True
            break  # Break the for loop when you find the first non-alpha. You can reduce the run-time with this solution.
    if not number_found:
        break
print("Correct input {}".format(name))

输出：

>>> python3 test.py # Success case
Enter name:test
Check t character
Check e character
Check s character
Check t character
Correct input test

>>> python3 test.py # Failed case
Enter name:test555
Check t character
Check e character
Check s character
Check t character
Check 5 character
5 is number. Try again.
Enter name:

【讨论】：