need help about textbox input logic

I will create a quiz to fill a textbox to answer, how can the answer is
not affected by the large or small letters? 
for example, the answer is 'Wonny' how when entering answers 'wonny' or 'WonnY' or 'WOnNy' can correct all? 
I confused this logic. please help



Use the upcase or downcase block.

upcase
Returns a copy of its text string argument converted to uppercase.
downcase
Returns a copy of its text string argument converted to lowercase.

e.g. if upcase(textbox1.text) = WONNY {
do something
}



Thank you .. very much :D