正则表达式以匹配单词和句点

Question

I wondering if anyone can help me finish a regex. I am trying to match the text after a keyword (phrase) and the period at the end of the sentence. I am close, but, no matter what I try, that period is always included.

Here is where I am currently:

phrase([^.]+?)\.

I know I could probably do something afterward like this:

string.replace(".",""); 

However, I would rather do everything I need via the regular expression. Can someone show me what part I am missing?

Example:

• Input: "The current phrase blah blah blah."
• Expected output: "blah blah blah"
• Current output: "blah blah blah." (period included.)

Answer 1

You need to either use your regex and get the Groups[1].Value from it:

var s = "My phrase is here.";
var rx = new Regex(@"phrase([^.]+)\.");
Console.WriteLine(rx.Match(s).Groups[1].Value);

See demo

Or re-write a regex with a look-behind and access the text you need using rx.Match(s).Value :

(?<=phrase)[^.]+

Code:

var rx = new Regex(@"(?<=phrase)[^.]+");
Console.WriteLine(rx.Match(s).Value);

See regex demo

NOTE : Look-behinds are resource-consuming, I'd definitely prefer the capturing group approach.

Answer 2

var blahs = Regex.Match(input, @"phrase(.+?)\.").Groups[1].Value;

Answer 3

Lookbehinds and lookaheads will allow you to match text before/after some other text, but not including the other text. In your example, you'll want (?<=The current phrase ).*?(?=\\.)