I think we need some more information. Specifically:
- How did you delete the file?
- Approximately how many lines of real code did you lose?
- Are you using any form of version control (Git? Mercurial?)
- Do you have any other forms of backup for your files?
If you're not backing up your information, this is going to happen and it's going to be terrible. I strongly advise you to start using Git (and Github) if you aren't already, to prevent this from happening in the future.