Replace everything except positive/negative numbers

问题

There are many questions already answered for replacing everything positive numbers. But, I couldn't find any answer which preserves both positive and negative numbers. I want to replace everything that isn't number(positive or negative). The output should be the following eg.

0 | success. id - 1234| -> 0 1234

and

-10 | failure. id - 2345| -> -10 2345

Apparently this answers for the positive part.

回答1:

You can use this regex to match positive/negative integers:

[+-]?\b\d+\b

RegEx Demo

to match positive/negative numbers including decimals:

[+-]?\b\d+(?:\.\d+)?\b

Please note that rather than using replace you would be better off using above regex in Pattern and Matcher APIs and just get your matched data.

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In case you can only use replace then use:

str = str.replaceAll( "([+-]?\\b\\d+\\b)|\\S+[ \\t]*", "$1" );

Replace Demo

来源：https://stackoverflow.com/questions/32421885/replace-everything-except-positive-negative-numbers