My regex is matching too much. How do I make it stop?
J0000000: Transaction A0001401 started on 8/22/2008 9:49:29 AM J0000010: Project name: E:foo.pf J0000011: Job name: MBiek Direct Mail Test J0000100: Machine name: DEV J0000100: Project file: E:mbiekfoo.pf J0000100: Template file: E:mbiekfoot.xdt J0000100: Job name: MBiek J0000100: Output folder: E:fooA0001401 J0000100: Temp folder: E:fooOutputA0001401 J0000100: Document 1 - Starting document J0005000: Document 1 - Text overflowed on page 1 (warning) J0000101: Document 1 - 1 page(s) composed J0000102: Document 1 - 1 page(s) rendered at 500 x 647 pixels J0000100: Document 1 - Completed successfully J0000020:
I have this gigantic ugly string and I'm trying to extract pieces from it using regex.
In this case, I want to grab everything after "Project Name" up to the part where it says "J0000011:" (the 11 is going to be a different number every time).
Here's the regex I've been playing with
Project name:s+(.*)s+J[0-9]{7}:
The problem is that it doesn't stop until it hits the J0000020: at the end.
How do I make the regex stop at the first occurrence of J[0-9]{7} ?
Make .* non-greedy by adding ' ? ' after it:
Project name:s+(.*?)s+J[0-9]{7}:
Using non-greedy quantifiers here is probably the best solution, also because it is more efficient than the greedy alternative: Greedy matches generally go as far as they can (here, until the end of the text!) and then trace back character after character to try and match the part coming afterwards.
Hower, consider using a negative character class instead:
Project name:s+(S*)s+J[0-9]{7}:
S means “everything except a whitespace and this is exactly what you want.
Well, ".*" is a greedy selector. You make it non-greedy by using ".*?" When using the latter construct, the regex engine will, at every step it matches text into the "." attempt to match whatever make come after the ".*?" . This means that if for instance nothing comes after the ".*?" , then it matches nothing.
Here's what I used. s contains your original string. This code is .NET specific, but most flavors of regex will have something similar.
string m = Regex.Match(s, @"Project name: (?<name>.*?) Jd+").Groups["name"].Value;
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