# Regular Expressions

**URL:** https://community.mp3tag.de/t/regular-expressions/521
**Category:** Howto
**Created:** [October 16, 2003, 4:47pm UTC](https://community.mp3tag.de/t/regular-expressions/521 "2003-10-16T16:47:29Z")
**Posts on this page:** 1
**Showing post:** 8

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### Author: ![ThurstonX](https://community.mp3tag.de/letter_avatar_proxy/v4/letter/t/ecae2f/32.png) [@ThurstonX](https://community.mp3tag.de/u/ThurstonX)
#### Post date: [July 31, 2004, 8:34pm UTC](https://community.mp3tag.de/t/regular-expressions/521/8 "2004-07-31T20:34:53Z")

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If you have a filename:

- 01 Trackname

and want it to be
- 01 - Trackname

create an Action with the following properties:
- Field: \_FILENAME
- Regular Expression: ([0-9]+)\s
- Replace matches with: $1 - $2

  
_Edit: Topic merged by moderator._

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