Java string.matches（）返回错误的语句

Question

I'm running some code through the eclipse debugger and a[1].matches("[a-zA-Z]") is not equating to true when a[1] = "ABCD" ( a is a string array).

I've read the javadoc on matches and [a-zA-Z] should be a valid regular expression..

Anyone know where I'm going wrong?

Answer 1

Try using this expression: [a-zA-Z]* (will match zero or more characters).

If you require at least one character, use: [a-zA-Z]+

The expression you're using will only match a single alpha character since it's not quantified .

Answer 2

Try a[1].matches("[a-zA-Z]+") . It says "one or more characters" must match instead of only a single character.

Note that '*' instead of '+' matches "zero or more characters' so it will match empty String (probably not what you want).

Answer 3

我认为它应该是a[1].matches("[a-zA-Z]*")

Answer 4

a[1].matches("[a-zA-Z\\s]+")  

可能有帮助

Answer 5

[a-zA-Z] would only accept a single letter. You probably need [a-zA-Z]* .

Answer 6

The reason that you're not matching that is string is that your RegEx expression is trying to match just a single character. Try this:

a[1].matches("[a-zA-Z]*")