Your problem has to do with variable scoping. Since you defined the played
, won
, lost
, draw
, & percent
variables within the button click handler, the variables are new each time the button is clicked. You need to move these variables so that they are defined outside of Button1_Click
.
This page on MSDN describes how variable scope works: http://msdn.microsoft.com/en-us/library/1t0wsc67.aspx
Right now those variables are in "procedure scope", but you need to make them "module scope" in order for them to preserve their values across button clicks.