Need Help: RegEx last number

Hello,
I have a RegEx problem. I want to rename files with the LAST number of the filename, but I don't know how to get it. Maybe someone here knows?

Here's a screenshot:
http://fs5.directupload.net/images/user/180512/ xhluu9x4.png

I always need the last number of the filename, complete, include the leading 0s.
Results should be like:
TestFolder-0125.txt
TestFolder-045.txt
TestFolder-44.txt
TestFolder-0015.txt
TestFolder-014.txt

Any idea?

---

Reply to #1:
Without a clearer distinction between the numbers you want to extract, I'm stumped.

---

Reply to #2:
Me too, but Thx 4 ur answer.
I now added a step before to remove text at the end. This works.

---