正则表达式（[A-Za-z] *）是否匹配数字和特殊字符？

Question

i need to validate a text fiel in my application. this cant contain neither digit nor special char so i tried this regex: [A-Za-z]* The problem is that this regex doesn't work when i put a digit or a special char in the middle or at the end of the String.

Answer 1

You should use it like this:

^[A-Za-z]+$

to match text (1 or more in length) containing ASCII letters only.

Answer 2

继续尝试^[A-Za-z]*$ 。

Answer 3

You could use the following Regex:

Pattern p = Pattern.compile("^[A-Za-z]*$");

See a list of regex-specs on http://docs.oracle.com/javase/1.4.2/docs/api/java/util/regex/Pattern.html

The pattern you describe will never work. Without the begin and end bonds the pattern will look for a substring that matches. Since an empty string is also allowed (star means 0 or more characters), one can simply use the empty string anywhere.

Answer 4

您正在检查是否可以帮助我验证日期时间类型YYYY-MM-DDThh：mm：ss.sssZ或YYYY-MM-DD

^(((19|20)[0-9][0-9])-(0?[1-9]|1[012])-(0?[1-9]|[12][0-9]|3[01]))|(((19|20)[0-9][0-9])-(0?[1-9]|1[012])-(0?[1-9]|[12][0-9]|3[01])T([01]?[0-9])|([2][0123]):([012345]?[0-9]):([012345]?[0-9])\.([0-9][0-9][0-9][Z]))$