为什么replaceAll会从字符串中删除数字？

Question

String foo = "a3#4#b";
String afterPunctutationRemoval = foo.replaceAll("[,.;:?!'-_\"/()\\{}]", "");
System.out.println(afterPunctutationRemoval);

it gives me "a##b" as a result, can someone explain me why?

Shouldn't it return the string as it is?

Answer 1

Your character class contains the range ' .. _ which matches digits as well.

Put the - at the start or end of the character class:

foo.replaceAll("[,.;:?!'_\"/()\\{}-]", "")

or escape it:

foo.replaceAll("[,.;:?!'\\-_\"/()\\{}]", "");

Answer 2

'-_匹配'和_之间'每个字符。

Answer 3

Like the other two people said, escape the - character - \\\\- .

Also, \\\\{ evaluates to the same as { , was this intended? If not, try escaping the backslash - \\\\\\\\{