将正则表达式限制为单词边界

Question

I have some text

"Lorem ipsum dolor sit amet, consectetuer adipiscing elit."

And I have a Regex, that is generated from user input.

@".*ip.*"

This matches the whole line, as you would expect, so I wrap this expression with word boundaries.

@"\b.*ip.*\b"

Because the processor is greedy, this still matches the whole text. So, I've tried making the repetition lazy.

@"\b.*?ip.*?\b"

This is better but matches

1. Lorem ipsum
2. dolor sit amet, consectetuer adipiscing

how can I extend the orginal @".*ip.*" pattern so that it lazily matches whole words and captures?

1. ipsum
2. adipiscing

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This regex tester maybe useful for answering the question

Answer 1

Why not just use \\w* instead of .*? :

@"\w*ip\w*"

This will also match _ and 0-9 as it is included in \\w . If you want to exclude it, you can use [a-zA-Z]* explicitly instead of \\w there.

Answer 2

You were already close to the solution. Just replace the dot (any char) by the non-whitespace escape sequence \\S:

@"\b\S*?ip\S*?\b"

Answer 3

我认为某些单词可以包含连字符，因此最好使用模式[\\w-]*ip[\\w-]*