Matching version number parts with regular expressions

Question

I'm trying to match the parts of a version number (Major.Minor.Build.Revision) with C# regular expressions. However, I'm pretty new to writing Regex and even using Expresso is proving to be a little difficult. Right now, I have this:

(?<Major>\d*)\.(?<Minor>\d*)\.(?<Build>\d*)\.(?<Revision>\d*)

This works, but requires that every part of the version number exists. What I would like to do is also match versions like:

2.13

In this case, the Build and Revision groups need to return null values. Feel free to suggest a better method if I'm going about this all wrong.

Answer 1

(?<Major>\d*)\.(?<Minor>\d*)(\.(?<Build>\d*)(\.(?<Revision>\d*))?)?

Makes the third and fourth parts optional.

Answer 2

I know this isn't a regex, but System.Version does all the work for you.