Getting Permission of a Directory in Program Files using C#

Question

I'm creating a setup to install my application.i have a button in my application which will create a text document in my Current Directory.After installing my application my Current Directory will be (C:\Program Files\Movie Database).but when creating that text document it is giving me an error saying, i don't have permission to create files in that directory.
How can i get permission to read/write files in my directory programmatically using C#.