Windows application

Question

I have a doubt in windows application
my doubt is
I have created a winform
for example
with two text boxes and two buttons
i have two different colours for two buttons
my question is if I click on a button, the colour of the button should be reflected on to the  background
like if I click on blue button the background should become blue..
How to do this give me example with code???
Thank u
chaithu