Regex: replace everything after underscore

Question

files are named like

name date _ uniqueid.pdf

result should be

name date _ somethingelse.pdf

I'll be using a find/replace so don't worry about the replace part. I just want to search matching the underscore.

This is NOT for c# .net, it is for find and replace in another program that accepts regex.

I'm really sorry I should've mentioned this. No languages, just plain regex. ie. /[^_].*

Thanks!

Answer 1

This is an example not taking into account any invalid characters in a file name

[^_]*_(.+)..+

Group 1 of that regex would return uniqueid in your first example. If you want to capture the file extension as well you can use the following.

[^_]*_(.+)

Edit:

C# Example with Regex.replace

//With file extension option
Regex.Replace(Test, "([^_]*_).+(\..+)", "$1somethingelse$2");

//Change file extension option
Regex.Replace(Test, "([^_]*_).+\..+", "$1somethingelse.pdf");