change file permission to 777 (c# 2010)

Please note: I need this code written in Microsoft visual studio 2010 express. I have some mp3 files that I want to upload to my server but before I upload them I want to change their permissions to 777 using c#. I've googled around and found some solutions but I would like someone that is an expert to get this done quick. This code can be to change the permission of ONE mp3 file. I can modify it to change the rest of the mp3 files. Contact me for questions.