Why can't my button access variables??

Question

In a hangman game I am trying to write using C#.Net I am trying to get a button to call a function but it can not use any variables I have defined earlier in the code.

Is there anyway that code added into the button can see variables that are stored outside of it?

I am new to this programming so please explain if I am missing something really obvious. Sorry!

Thanks for any help guys.
Dan