用正则表达式替换“ [”和“]”

Question

I want a regular experssion for java to replace the "[" and the "]" . the compiler give error because [ is the syntax of regex. what should i do?

Answer 1

You just need to escape the special characters - \\[ and \\] . This applies to all special characters too.

Answer 2

backslashes! for any character that has a special meaning, you preface it with a backslash to match the literal character.

Pattern = Pattern.compile("\\[\\]"); 

(pay attention that because it's java, you need two backslashes to equate to one backslash char).

Answer 3

You could do:

String s = ...
s = s.replaceAll("\\[|]", "");

or:

s = s.replaceAll("[[\\]]", "");

or a non-regex replacement (so no escaping needed):

s = s.replace("[", "").replace("]", "");

An explanation of the regexes (the first 2 examples):

1: \\\\[|]

\\[    # match `[`
|      # OR
]      # match ']'

2: [[\\\\]]

[      # start character class
  [    # match '[', or
  \\]  # match ']'
]      # end character class

Answer 4

Normally you can escape special characters with backslashes

\\[

or

\\]