String Python字符串检查

有人能告诉我如何检查用户的输入是否包含数字，并且只包含数字和字母吗

以下是我到目前为止的情况：

employNum = input("Please enter your employee ID: ")

if len(employNum) == 8:
    print("This is a valid employee ID.")

我想在所有检查完成后打印最后一份报表。我只是不知道如何检查字符串

.alnum（）

测试字符串是否都是字母数字。如果您至少需要一个数字，则使用

.isdigit（）

单独测试这些数字，并使用

any（）

查找至少一个：

>>> employNum = input("Please enter your employee ID: ")
Please enter your employee ID: asdf890
>>> all(i.isalpha() or i.isdigit() for i in employNum)
True
>>> employNum = input("Please enter your employee ID: ")
Please enter your employee ID: asdfjie-09
>>> all(i.isalpha() or i.isdigit() for i in employNum)
False


>>> def threeNums(s):
...   return sum(1 for char in s if char.isdigit())==3
... 
>>> def atLeastThreeNums(s):
...   return sum(1 for char in s if char.isdigit())>=3
... 
>>> def threeChars(s):
...   return sum(1 for char in s if char.isalpha())==3
... 
>>> def atLeastThreeChars(s):
...   return sum(1 for char in s if char.isalpha())>=3
... 
>>> rules = [threeNums, threeChars]
>>> employNum = input("Please enter your employee ID: ")
Please enter your employee ID: asdf02
>>> all(rule(employNum) for rule in rules)
False
>>> employNum = input("Please enter your employee ID: ")
Please enter your employee ID: asdf012
>>> all(rule(employNum) for rule in rules)
False
>>> employNum = input("Please enter your employee ID: ")
Please enter your employee ID: asd123
>>> all(rule(employNum) for rule in rules)
True

---

参考资料：

哇，太快了。非常感谢。有没有办法检查是否有一定数量的字母或数字？例如，如果employNum必须包含3个数字？@WhooCares：检查编辑。如果您想要更严格的检查，您可以查看正则表达式（如果您想让我写出来，请发表评论）

employNum = input("Please enter your employee ID: ")

if len(employNum) == 8 and employNum.isalnum() and any(n.isdigit() for n in employNum):
    print("This is a valid employee ID.")