Case sensitive in regular expression

Question

I´m new to regular expressions, I need find one phrase in a piece of text (case insensitive), for example:

Text : FindThis("This is example text")

I need get "FindThis" to locate my phrase regardless of the case of the text.

I've tried this:

static Regex text= new Regex("(FindThis\\(['|\"])([^'\"]*)");

By default a Regex is done in a case sensitive manner. Can you try and explain what is going wrong by providing samples that you expect should match and don't? — JaredPar
– JaredPar, Commented Dec 17, 2013 at 17:03
Experiment. Sites like rubular.com are awesome for this. Regexes are, indeed, case sensitive by default (unless you add the i flag at the end). — ashes999
– ashes999, Commented Dec 17, 2013 at 17:05
Thanks for the responses, and I understand, the regular expression is case sensitive by default, but, in my example if I change the example test for "FiNdThIs("This is example text")" is not mached, I´m explain? — user3099253
– user3099253, Commented Dec 17, 2013 at 17:13
Are you saying that you'd like it to be matched regardless of case? — Liath
– Liath, Commented Dec 17, 2013 at 17:14
I say that in my example when I change one letter per upper or lower case, the regular expression stops working (in my example) — user3099253
– user3099253, Commented Dec 17, 2013 at 17:18

Doug Dawson · Accepted Answer · 2013-12-17 17:03:06Z

3

Case sensitive should be "on" by default. You can pass the option to ignore case when you do the match.

Here's an example: http://www.dotnetperls.com/regex

answered Dec 17, 2013 at 17:03

Doug Dawson

1,2732 gold badges21 silver badges38 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

user3099253 Over a year ago

Thanks for the response, but, in my example if I change the example test for "FiNdThIs("This is example text")" is not mached, I´m explain?

Doug Dawson Over a year ago

You'll need to post more code. You show the RegEx being created, but there should be a regEx.Match method with an input string. What's the rest of your code look like?

user3099253 Over a year ago

Don´t worry, I resolved this another way, anyway, thank you very much

Liath · Accepted Answer · 2013-12-17 17:31:50Z

You can do this by using the RegexOptions.IgnoreCase enum. Here's an example:

var result = Regex.IsMatch("Here's some FINDTHIS Text", // the text to search in
                "FindThis", // this is the text we're looking for
                RegexOptions.IgnoreCase); // specifies that it's not case sensitive

Note that in this case our regex pattern is actually just the text we're looking for. It could equally be a much more complex pattern.

I would check that the Contains method doesn't do what you're looking for? It's a lot simpler!

was not what I was looking for, but I used it anyway, thank you very much! (sorry for my english)

Collectives™ on Stack Overflow

Case sensitive in regular expression

2 Answers 2

3 Comments

1 Comment

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

3 Comments

1 Comment

Related